A256237 Primes p such that for all 2^k < p the numbers p + 2^k, p - 2^k, p*2^k + 1, and p*2^k - 1 are composite.

8923, 24943, 35437, 42533, 52783, 83437, 105953, 116437, 126631, 133241, 145589, 164729, 172331, 192173, 204013, 215279, 254329, 304709, 308899, 398833, 430499, 436687, 454351, 476869, 479909, 483443, 497597, 522479, 527729, 529103, 545257, 561439, 562651

Offset

1,1

Links

Table of n, a(n) for n=1..33.

Prog

(Magma) lst:=[]; for p in [3..562651 by 2] do if IsPrime(p) then t:=0; k:=0; while 2^k lt p do if IsPrime(p-2^k) or IsPrime(p+2^k) or IsPrime(p*2^k-1) or IsPrime(p*2^k+1) then t:=1; break; end if; k+:=1; end while; if IsZero(t) then Append(~lst, p); end if; end if; end for; lst;

Crossrefs

Subsequence of A256163.

Cf. A006285, A065381, A153352, A180247, A255967.

Sequence in context: A329468 A185321 A267462 * A065235 A087167 A290811

Adjacent sequences: A256234 A256235 A256236 * A256238 A256239 A256240

Keyword

nonn

Author

Arkadiusz Wesolowski, Mar 20 2015

Status

approved