A222227 Numbers n such that n and n + 16 are prime and there is a power of two in the interval (n,n+16).
3, 7, 13, 31, 241, 65521, 1048573, 2305843009213693951
Offset: 1
Keywords
Programs
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Magma
//Program finds primes separated by an even number (called gap) which //have a power of two between them. Program starts with the smallest //power of two above gap. Primes less than this starting point can be //checked by inspection. gap:=16; start:=Ilog2(gap)+1; for i:= start to 1000 do powerof2:=2^i; for k:=powerof2-gap+1 to powerof2-1 by 2 do if (IsPrime(k) and IsPrime(k+gap)) then k; end if; end for; end for;
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