cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A269258 Primes p such that p+2^4, p+2^6, p+2^8 and p+2^10 are all primes.

Original entry on oeis.org

7, 37, 163, 337, 2647, 5023, 9157, 9277, 15667, 22093, 24907, 40177, 43597, 47287, 53593, 56893, 59077, 59497, 66553, 78877, 83407, 84793, 92737, 93307, 102043, 111577, 114577, 116953, 120607, 135193, 137383, 141397, 142543, 150067, 165463, 173713, 180007, 181903, 183943
Offset: 1

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Examples

			The prime 7 is in the sequence because 7+16 = 23, 7+64 = 71, 7+256 = 263 and 7+1024 = 1031 are all primes.
The prime 37 is in the sequence because 37+16 = 53, 37+64 = 101, 37+256 = 293 and 37+1024 = 1061 are all primes.
		

Crossrefs

Subsequence of A269257.

Programs

  • Magma
    [p: p in PrimesInInterval(2,200000) | forall{i: i in [16,64,256,1024] | IsPrime(p+i)}]; // Vincenzo Librandi, Jul 16 2016
  • Mathematica
    Select[Prime@ Range[10^5], Times @@ Boole@ PrimeQ[# + 2^{4, 6, 8, 10}] == 1 &] (* Michael De Vlieger, Jul 13 2016 *)
  • Perl
    use ntheory ":all"; say for sieve_prime_cluster(2,1e5, 16,64,256,1024); # Dana Jacobsen, Jul 13 2016
    

Formula

A269257 INTERSECT A361485. - R. J. Mathar, Mar 26 2024