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A139122
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Primes whose binary representation shows the distribution of prime numbers up to some prime minus 1, using "0" for primes and "1" for nonprime numbers.
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5
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OFFSET
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1,1
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COMMENTS
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LINKS
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MATHEMATICA
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Select[Table[ sum = 0; For[i = 1, i <= Prime[n] - 1 , i++, sum = sum*2; If[! PrimeQ[i], sum++]]; sum, {n, 1, 1000}], PrimeQ[#] &] (* Robert Price, Apr 03 2019 *)
Module[{nn=500, p, x}, p=Table[If[PrimeQ[n], 0, 1], {n, nn}]; x=SequencePosition[p, {1, 0}][[All, 1]]; Join[{2}, Select[Table[FromDigits[Take[p, k], 2], {k, x}], PrimeQ]]] (* Harvey P. Dale, Jun 15 2022 *)
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PROG
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(PARI) f(n) = fromdigits(vector(prime(n)-1, k, !isprime(k)), 2); \\ A139102
lista(nn) = for (n=1, nn, if (isprime(p=f(n)), print1(p, ", ")));
from sympy import isprime
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CROSSREFS
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KEYWORD
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nonn,base,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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