Search for very large prime (greater than $2^{57885161} − 1$) between Crystal Numbers
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0
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Denote $p[i]$ as the $i$th prime. In my opinion, the following is true:
Prime Gap Axiom
There are always distinct prime factors for ${p[i],p[i]+1,p[i]+2, dots , p[i+1]}$.
Question 1
How to give some good algorithm to dispatch distinct prime factors?
Corollary 1
$p[i+1]-p[i]le 1+pi( p[i+1]/2 ) le i$, for any integer $ige 1$;
There exists at least one prime in the interval $( n,n+pi(n)]$.
Corollary 2
Define Crystal Number Sequence, Crystal(2,3)={2^i* 3^j|i>=0,j>=0}, then the interval ( Crystal[n],Crystal[n+2]) contains at least one prime, for any $nge 1$.
Clearly, Crystal Numbers are very related with Mersenne numbers.
indexTop = 30;
Crystal[p1_, p2_] :=
Sort@Flatten@Table[p1^i*p2^j, {i, 0, indexTop}, {j, 0, indexTop}]
list = Take[Crystal[2, 3], indexTop]
Graphics[Point[{#, 0}] & /@ list,
Epilog -> {Orange, Point[Table[{Prime[k], 0}, {k, 1, indexTop}]]}]
Question 2:
Can we find (very large) three close numbers c1,c2,c3 which are alike $2^i*3^j$?
exclude composite numbers of the interval (c1, c3) , if there is only one survivor, it must be prime! Is this method feasible? will it be much greater than $2^{57885161} − 1$ ?
Link to Mathematica Notebook
number-theory prime-numbers prime-gaps
add a comment |
up vote
0
down vote
favorite
Denote $p[i]$ as the $i$th prime. In my opinion, the following is true:
Prime Gap Axiom
There are always distinct prime factors for ${p[i],p[i]+1,p[i]+2, dots , p[i+1]}$.
Question 1
How to give some good algorithm to dispatch distinct prime factors?
Corollary 1
$p[i+1]-p[i]le 1+pi( p[i+1]/2 ) le i$, for any integer $ige 1$;
There exists at least one prime in the interval $( n,n+pi(n)]$.
Corollary 2
Define Crystal Number Sequence, Crystal(2,3)={2^i* 3^j|i>=0,j>=0}, then the interval ( Crystal[n],Crystal[n+2]) contains at least one prime, for any $nge 1$.
Clearly, Crystal Numbers are very related with Mersenne numbers.
indexTop = 30;
Crystal[p1_, p2_] :=
Sort@Flatten@Table[p1^i*p2^j, {i, 0, indexTop}, {j, 0, indexTop}]
list = Take[Crystal[2, 3], indexTop]
Graphics[Point[{#, 0}] & /@ list,
Epilog -> {Orange, Point[Table[{Prime[k], 0}, {k, 1, indexTop}]]}]
Question 2:
Can we find (very large) three close numbers c1,c2,c3 which are alike $2^i*3^j$?
exclude composite numbers of the interval (c1, c3) , if there is only one survivor, it must be prime! Is this method feasible? will it be much greater than $2^{57885161} − 1$ ?
Link to Mathematica Notebook
number-theory prime-numbers prime-gaps
For example, {13,14,15,16,17} have distinct prime factors {13,7,3,2,17}; {113,114,115,116,117,118,119,120,121,122,123,124,125,126,127} have distinct prime factors {113,19, 23, 29, 13, 59, 17, 2, 11, 61, 41, 31, 5, 3, 127}
– a boy
Oct 18 '14 at 3:47
2
I tried to improve formatting... can't say it was a complete success. Please review the post.
– user147263
Oct 19 '14 at 5:18
The "Crystal Numbers" are tabulated, with much information and links, at oeis.org/A003586
– Gerry Myerson
Oct 19 '14 at 5:22
1
If you take the log of $2^i3^j$, you get $i log 2 + j log 3$. To find close Crystal numbers, you want to find $i,j$ such that $-i log 2 + j log 3$ is rather small. One example is $i=3, j=2$, corresponding to $2^3=8,3^2=9$. The corresponding $c_1,c_2,c_3$ are $2^{2i},2^i3^j,3^{2j}$. For my example, this is $64,72,81$ and there are $67,71,73,79$ as primes in the range. You can use continued fractions to find better approximations to the ratio of the logs. The prime number theorem will let you estimate the number of primes, but it won't prove there is at least one.
– Ross Millikan
Oct 20 '14 at 4:41
What do you mean by "distinct prime factors"? $p[i]+2k+1$ will always have $2$ as prime factors for all $kgeq 0$.
– Klangen
Nov 23 at 10:36
add a comment |
up vote
0
down vote
favorite
up vote
0
down vote
favorite
Denote $p[i]$ as the $i$th prime. In my opinion, the following is true:
Prime Gap Axiom
There are always distinct prime factors for ${p[i],p[i]+1,p[i]+2, dots , p[i+1]}$.
Question 1
How to give some good algorithm to dispatch distinct prime factors?
Corollary 1
$p[i+1]-p[i]le 1+pi( p[i+1]/2 ) le i$, for any integer $ige 1$;
There exists at least one prime in the interval $( n,n+pi(n)]$.
Corollary 2
Define Crystal Number Sequence, Crystal(2,3)={2^i* 3^j|i>=0,j>=0}, then the interval ( Crystal[n],Crystal[n+2]) contains at least one prime, for any $nge 1$.
Clearly, Crystal Numbers are very related with Mersenne numbers.
indexTop = 30;
Crystal[p1_, p2_] :=
Sort@Flatten@Table[p1^i*p2^j, {i, 0, indexTop}, {j, 0, indexTop}]
list = Take[Crystal[2, 3], indexTop]
Graphics[Point[{#, 0}] & /@ list,
Epilog -> {Orange, Point[Table[{Prime[k], 0}, {k, 1, indexTop}]]}]
Question 2:
Can we find (very large) three close numbers c1,c2,c3 which are alike $2^i*3^j$?
exclude composite numbers of the interval (c1, c3) , if there is only one survivor, it must be prime! Is this method feasible? will it be much greater than $2^{57885161} − 1$ ?
Link to Mathematica Notebook
number-theory prime-numbers prime-gaps
Denote $p[i]$ as the $i$th prime. In my opinion, the following is true:
Prime Gap Axiom
There are always distinct prime factors for ${p[i],p[i]+1,p[i]+2, dots , p[i+1]}$.
Question 1
How to give some good algorithm to dispatch distinct prime factors?
Corollary 1
$p[i+1]-p[i]le 1+pi( p[i+1]/2 ) le i$, for any integer $ige 1$;
There exists at least one prime in the interval $( n,n+pi(n)]$.
Corollary 2
Define Crystal Number Sequence, Crystal(2,3)={2^i* 3^j|i>=0,j>=0}, then the interval ( Crystal[n],Crystal[n+2]) contains at least one prime, for any $nge 1$.
Clearly, Crystal Numbers are very related with Mersenne numbers.
indexTop = 30;
Crystal[p1_, p2_] :=
Sort@Flatten@Table[p1^i*p2^j, {i, 0, indexTop}, {j, 0, indexTop}]
list = Take[Crystal[2, 3], indexTop]
Graphics[Point[{#, 0}] & /@ list,
Epilog -> {Orange, Point[Table[{Prime[k], 0}, {k, 1, indexTop}]]}]
Question 2:
Can we find (very large) three close numbers c1,c2,c3 which are alike $2^i*3^j$?
exclude composite numbers of the interval (c1, c3) , if there is only one survivor, it must be prime! Is this method feasible? will it be much greater than $2^{57885161} − 1$ ?
Link to Mathematica Notebook
number-theory prime-numbers prime-gaps
number-theory prime-numbers prime-gaps
edited Nov 23 at 10:40
amWhy
191k27223439
191k27223439
asked Oct 18 '14 at 3:46
a boy
422211
422211
For example, {13,14,15,16,17} have distinct prime factors {13,7,3,2,17}; {113,114,115,116,117,118,119,120,121,122,123,124,125,126,127} have distinct prime factors {113,19, 23, 29, 13, 59, 17, 2, 11, 61, 41, 31, 5, 3, 127}
– a boy
Oct 18 '14 at 3:47
2
I tried to improve formatting... can't say it was a complete success. Please review the post.
– user147263
Oct 19 '14 at 5:18
The "Crystal Numbers" are tabulated, with much information and links, at oeis.org/A003586
– Gerry Myerson
Oct 19 '14 at 5:22
1
If you take the log of $2^i3^j$, you get $i log 2 + j log 3$. To find close Crystal numbers, you want to find $i,j$ such that $-i log 2 + j log 3$ is rather small. One example is $i=3, j=2$, corresponding to $2^3=8,3^2=9$. The corresponding $c_1,c_2,c_3$ are $2^{2i},2^i3^j,3^{2j}$. For my example, this is $64,72,81$ and there are $67,71,73,79$ as primes in the range. You can use continued fractions to find better approximations to the ratio of the logs. The prime number theorem will let you estimate the number of primes, but it won't prove there is at least one.
– Ross Millikan
Oct 20 '14 at 4:41
What do you mean by "distinct prime factors"? $p[i]+2k+1$ will always have $2$ as prime factors for all $kgeq 0$.
– Klangen
Nov 23 at 10:36
add a comment |
For example, {13,14,15,16,17} have distinct prime factors {13,7,3,2,17}; {113,114,115,116,117,118,119,120,121,122,123,124,125,126,127} have distinct prime factors {113,19, 23, 29, 13, 59, 17, 2, 11, 61, 41, 31, 5, 3, 127}
– a boy
Oct 18 '14 at 3:47
2
I tried to improve formatting... can't say it was a complete success. Please review the post.
– user147263
Oct 19 '14 at 5:18
The "Crystal Numbers" are tabulated, with much information and links, at oeis.org/A003586
– Gerry Myerson
Oct 19 '14 at 5:22
1
If you take the log of $2^i3^j$, you get $i log 2 + j log 3$. To find close Crystal numbers, you want to find $i,j$ such that $-i log 2 + j log 3$ is rather small. One example is $i=3, j=2$, corresponding to $2^3=8,3^2=9$. The corresponding $c_1,c_2,c_3$ are $2^{2i},2^i3^j,3^{2j}$. For my example, this is $64,72,81$ and there are $67,71,73,79$ as primes in the range. You can use continued fractions to find better approximations to the ratio of the logs. The prime number theorem will let you estimate the number of primes, but it won't prove there is at least one.
– Ross Millikan
Oct 20 '14 at 4:41
What do you mean by "distinct prime factors"? $p[i]+2k+1$ will always have $2$ as prime factors for all $kgeq 0$.
– Klangen
Nov 23 at 10:36
For example, {13,14,15,16,17} have distinct prime factors {13,7,3,2,17}; {113,114,115,116,117,118,119,120,121,122,123,124,125,126,127} have distinct prime factors {113,19, 23, 29, 13, 59, 17, 2, 11, 61, 41, 31, 5, 3, 127}
– a boy
Oct 18 '14 at 3:47
For example, {13,14,15,16,17} have distinct prime factors {13,7,3,2,17}; {113,114,115,116,117,118,119,120,121,122,123,124,125,126,127} have distinct prime factors {113,19, 23, 29, 13, 59, 17, 2, 11, 61, 41, 31, 5, 3, 127}
– a boy
Oct 18 '14 at 3:47
2
2
I tried to improve formatting... can't say it was a complete success. Please review the post.
– user147263
Oct 19 '14 at 5:18
I tried to improve formatting... can't say it was a complete success. Please review the post.
– user147263
Oct 19 '14 at 5:18
The "Crystal Numbers" are tabulated, with much information and links, at oeis.org/A003586
– Gerry Myerson
Oct 19 '14 at 5:22
The "Crystal Numbers" are tabulated, with much information and links, at oeis.org/A003586
– Gerry Myerson
Oct 19 '14 at 5:22
1
1
If you take the log of $2^i3^j$, you get $i log 2 + j log 3$. To find close Crystal numbers, you want to find $i,j$ such that $-i log 2 + j log 3$ is rather small. One example is $i=3, j=2$, corresponding to $2^3=8,3^2=9$. The corresponding $c_1,c_2,c_3$ are $2^{2i},2^i3^j,3^{2j}$. For my example, this is $64,72,81$ and there are $67,71,73,79$ as primes in the range. You can use continued fractions to find better approximations to the ratio of the logs. The prime number theorem will let you estimate the number of primes, but it won't prove there is at least one.
– Ross Millikan
Oct 20 '14 at 4:41
If you take the log of $2^i3^j$, you get $i log 2 + j log 3$. To find close Crystal numbers, you want to find $i,j$ such that $-i log 2 + j log 3$ is rather small. One example is $i=3, j=2$, corresponding to $2^3=8,3^2=9$. The corresponding $c_1,c_2,c_3$ are $2^{2i},2^i3^j,3^{2j}$. For my example, this is $64,72,81$ and there are $67,71,73,79$ as primes in the range. You can use continued fractions to find better approximations to the ratio of the logs. The prime number theorem will let you estimate the number of primes, but it won't prove there is at least one.
– Ross Millikan
Oct 20 '14 at 4:41
What do you mean by "distinct prime factors"? $p[i]+2k+1$ will always have $2$ as prime factors for all $kgeq 0$.
– Klangen
Nov 23 at 10:36
What do you mean by "distinct prime factors"? $p[i]+2k+1$ will always have $2$ as prime factors for all $kgeq 0$.
– Klangen
Nov 23 at 10:36
add a comment |
1 Answer
1
active
oldest
votes
up vote
0
down vote
Today, I had found an iterative algorithm to dispatch prime factors. Suppose we has the proper primeFactorsList for {1,2,3,...,n-1}, now considering n, n has PrimeNu(n) prime factors, we choose the one that is not dispatched most recently!
(*Dispatch Prime Factors for n<128 *)
reversePrimeFactorsList = {3, 2, 1};
n = 3;
i = 2;
PrimeFactors[x_] := FactorInteger[x][[All, 1]];
While[n < 128,
n++; If[PrimeQ[n], i++; PrependTo [reversePrimeFactorsList, n],
pos = Max[
FirstPosition[reversePrimeFactorsList, #] & /@ PrimeFactors[n]
];
PrependTo[reversePrimeFactorsList, reversePrimeFactorsList[[pos]]]
(*choose the one that is not used most recently*)
]
];
{i, Prime[i], n}
reversePrimeFactorsList
ListPlot[{Range[n], Reverse@reversePrimeFactorsList}, Filling -> Axis]
Out34:= {31, 127, 128}
Out35:= {2, 127, 3, 5, 31, 41, 61, 11, 5, 17, 59, 13, 29, 23, 19, 113, 7, 37,
11, 109, 2, 107, 53, 3, 2, 103, 17, 101, 5, 11, 7, 97, 3, 19, 47, 31,
23, 13, 2, 89, 11, 29, 43, 17, 7, 83, 41, 3, 5, 79, 2, 11, 19, 5, 37,
73, 3, 71, 7, 23, 17, 67, 11, 13, 2, 3, 31, 61, 5, 59, 29, 19, 7, 11,
3, 53, 13, 17, 2, 7, 3, 47, 23, 5, 11, 43, 7, 41, 2, 13, 19, 37, 3,
5, 17, 11, 2, 31, 2, 29, 7, 3, 13, 5, 2, 23, 11, 7, 5, 19, 3, 17, 2,
3, 7, 13, 2, 11, 5, 3, 2, 7, 3, 5, 2, 3, 2, 1}
add a comment |
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
0
down vote
Today, I had found an iterative algorithm to dispatch prime factors. Suppose we has the proper primeFactorsList for {1,2,3,...,n-1}, now considering n, n has PrimeNu(n) prime factors, we choose the one that is not dispatched most recently!
(*Dispatch Prime Factors for n<128 *)
reversePrimeFactorsList = {3, 2, 1};
n = 3;
i = 2;
PrimeFactors[x_] := FactorInteger[x][[All, 1]];
While[n < 128,
n++; If[PrimeQ[n], i++; PrependTo [reversePrimeFactorsList, n],
pos = Max[
FirstPosition[reversePrimeFactorsList, #] & /@ PrimeFactors[n]
];
PrependTo[reversePrimeFactorsList, reversePrimeFactorsList[[pos]]]
(*choose the one that is not used most recently*)
]
];
{i, Prime[i], n}
reversePrimeFactorsList
ListPlot[{Range[n], Reverse@reversePrimeFactorsList}, Filling -> Axis]
Out34:= {31, 127, 128}
Out35:= {2, 127, 3, 5, 31, 41, 61, 11, 5, 17, 59, 13, 29, 23, 19, 113, 7, 37,
11, 109, 2, 107, 53, 3, 2, 103, 17, 101, 5, 11, 7, 97, 3, 19, 47, 31,
23, 13, 2, 89, 11, 29, 43, 17, 7, 83, 41, 3, 5, 79, 2, 11, 19, 5, 37,
73, 3, 71, 7, 23, 17, 67, 11, 13, 2, 3, 31, 61, 5, 59, 29, 19, 7, 11,
3, 53, 13, 17, 2, 7, 3, 47, 23, 5, 11, 43, 7, 41, 2, 13, 19, 37, 3,
5, 17, 11, 2, 31, 2, 29, 7, 3, 13, 5, 2, 23, 11, 7, 5, 19, 3, 17, 2,
3, 7, 13, 2, 11, 5, 3, 2, 7, 3, 5, 2, 3, 2, 1}
add a comment |
up vote
0
down vote
Today, I had found an iterative algorithm to dispatch prime factors. Suppose we has the proper primeFactorsList for {1,2,3,...,n-1}, now considering n, n has PrimeNu(n) prime factors, we choose the one that is not dispatched most recently!
(*Dispatch Prime Factors for n<128 *)
reversePrimeFactorsList = {3, 2, 1};
n = 3;
i = 2;
PrimeFactors[x_] := FactorInteger[x][[All, 1]];
While[n < 128,
n++; If[PrimeQ[n], i++; PrependTo [reversePrimeFactorsList, n],
pos = Max[
FirstPosition[reversePrimeFactorsList, #] & /@ PrimeFactors[n]
];
PrependTo[reversePrimeFactorsList, reversePrimeFactorsList[[pos]]]
(*choose the one that is not used most recently*)
]
];
{i, Prime[i], n}
reversePrimeFactorsList
ListPlot[{Range[n], Reverse@reversePrimeFactorsList}, Filling -> Axis]
Out34:= {31, 127, 128}
Out35:= {2, 127, 3, 5, 31, 41, 61, 11, 5, 17, 59, 13, 29, 23, 19, 113, 7, 37,
11, 109, 2, 107, 53, 3, 2, 103, 17, 101, 5, 11, 7, 97, 3, 19, 47, 31,
23, 13, 2, 89, 11, 29, 43, 17, 7, 83, 41, 3, 5, 79, 2, 11, 19, 5, 37,
73, 3, 71, 7, 23, 17, 67, 11, 13, 2, 3, 31, 61, 5, 59, 29, 19, 7, 11,
3, 53, 13, 17, 2, 7, 3, 47, 23, 5, 11, 43, 7, 41, 2, 13, 19, 37, 3,
5, 17, 11, 2, 31, 2, 29, 7, 3, 13, 5, 2, 23, 11, 7, 5, 19, 3, 17, 2,
3, 7, 13, 2, 11, 5, 3, 2, 7, 3, 5, 2, 3, 2, 1}
add a comment |
up vote
0
down vote
up vote
0
down vote
Today, I had found an iterative algorithm to dispatch prime factors. Suppose we has the proper primeFactorsList for {1,2,3,...,n-1}, now considering n, n has PrimeNu(n) prime factors, we choose the one that is not dispatched most recently!
(*Dispatch Prime Factors for n<128 *)
reversePrimeFactorsList = {3, 2, 1};
n = 3;
i = 2;
PrimeFactors[x_] := FactorInteger[x][[All, 1]];
While[n < 128,
n++; If[PrimeQ[n], i++; PrependTo [reversePrimeFactorsList, n],
pos = Max[
FirstPosition[reversePrimeFactorsList, #] & /@ PrimeFactors[n]
];
PrependTo[reversePrimeFactorsList, reversePrimeFactorsList[[pos]]]
(*choose the one that is not used most recently*)
]
];
{i, Prime[i], n}
reversePrimeFactorsList
ListPlot[{Range[n], Reverse@reversePrimeFactorsList}, Filling -> Axis]
Out34:= {31, 127, 128}
Out35:= {2, 127, 3, 5, 31, 41, 61, 11, 5, 17, 59, 13, 29, 23, 19, 113, 7, 37,
11, 109, 2, 107, 53, 3, 2, 103, 17, 101, 5, 11, 7, 97, 3, 19, 47, 31,
23, 13, 2, 89, 11, 29, 43, 17, 7, 83, 41, 3, 5, 79, 2, 11, 19, 5, 37,
73, 3, 71, 7, 23, 17, 67, 11, 13, 2, 3, 31, 61, 5, 59, 29, 19, 7, 11,
3, 53, 13, 17, 2, 7, 3, 47, 23, 5, 11, 43, 7, 41, 2, 13, 19, 37, 3,
5, 17, 11, 2, 31, 2, 29, 7, 3, 13, 5, 2, 23, 11, 7, 5, 19, 3, 17, 2,
3, 7, 13, 2, 11, 5, 3, 2, 7, 3, 5, 2, 3, 2, 1}
Today, I had found an iterative algorithm to dispatch prime factors. Suppose we has the proper primeFactorsList for {1,2,3,...,n-1}, now considering n, n has PrimeNu(n) prime factors, we choose the one that is not dispatched most recently!
(*Dispatch Prime Factors for n<128 *)
reversePrimeFactorsList = {3, 2, 1};
n = 3;
i = 2;
PrimeFactors[x_] := FactorInteger[x][[All, 1]];
While[n < 128,
n++; If[PrimeQ[n], i++; PrependTo [reversePrimeFactorsList, n],
pos = Max[
FirstPosition[reversePrimeFactorsList, #] & /@ PrimeFactors[n]
];
PrependTo[reversePrimeFactorsList, reversePrimeFactorsList[[pos]]]
(*choose the one that is not used most recently*)
]
];
{i, Prime[i], n}
reversePrimeFactorsList
ListPlot[{Range[n], Reverse@reversePrimeFactorsList}, Filling -> Axis]
Out34:= {31, 127, 128}
Out35:= {2, 127, 3, 5, 31, 41, 61, 11, 5, 17, 59, 13, 29, 23, 19, 113, 7, 37,
11, 109, 2, 107, 53, 3, 2, 103, 17, 101, 5, 11, 7, 97, 3, 19, 47, 31,
23, 13, 2, 89, 11, 29, 43, 17, 7, 83, 41, 3, 5, 79, 2, 11, 19, 5, 37,
73, 3, 71, 7, 23, 17, 67, 11, 13, 2, 3, 31, 61, 5, 59, 29, 19, 7, 11,
3, 53, 13, 17, 2, 7, 3, 47, 23, 5, 11, 43, 7, 41, 2, 13, 19, 37, 3,
5, 17, 11, 2, 31, 2, 29, 7, 3, 13, 5, 2, 23, 11, 7, 5, 19, 3, 17, 2,
3, 7, 13, 2, 11, 5, 3, 2, 7, 3, 5, 2, 3, 2, 1}
answered Oct 20 '14 at 4:26
a boy
422211
422211
add a comment |
add a comment |
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For example, {13,14,15,16,17} have distinct prime factors {13,7,3,2,17}; {113,114,115,116,117,118,119,120,121,122,123,124,125,126,127} have distinct prime factors {113,19, 23, 29, 13, 59, 17, 2, 11, 61, 41, 31, 5, 3, 127}
– a boy
Oct 18 '14 at 3:47
2
I tried to improve formatting... can't say it was a complete success. Please review the post.
– user147263
Oct 19 '14 at 5:18
The "Crystal Numbers" are tabulated, with much information and links, at oeis.org/A003586
– Gerry Myerson
Oct 19 '14 at 5:22
1
If you take the log of $2^i3^j$, you get $i log 2 + j log 3$. To find close Crystal numbers, you want to find $i,j$ such that $-i log 2 + j log 3$ is rather small. One example is $i=3, j=2$, corresponding to $2^3=8,3^2=9$. The corresponding $c_1,c_2,c_3$ are $2^{2i},2^i3^j,3^{2j}$. For my example, this is $64,72,81$ and there are $67,71,73,79$ as primes in the range. You can use continued fractions to find better approximations to the ratio of the logs. The prime number theorem will let you estimate the number of primes, but it won't prove there is at least one.
– Ross Millikan
Oct 20 '14 at 4:41
What do you mean by "distinct prime factors"? $p[i]+2k+1$ will always have $2$ as prime factors for all $kgeq 0$.
– Klangen
Nov 23 at 10:36