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%I #14 Feb 04 2023 09:58:30
%S 2,3,5,17,31,41,47,53,59,73,79,89,97,103,109,113,127,137,149,163,167,
%T 173,179,191,193,197,223,227,233,239,251,257,271,277,281,283,307,311,
%U 313,331,337,347,349,367,373,379,389,397,401,409,421,431,433,439,443
%N Primes that cannot be written as 2^k + p with p prime < 2^k.
%C A118953(A049084(a(n))) = 0; A065381 is a subsequence.
%H Robert Israel, <a href="/A118958/b118958.txt">Table of n, a(n) for n = 1..10000</a>
%p filter:= proc(n) not isprime(n-2^ilog2(n)) end proc:
%p select(filter, [seq(ithprime(i),i=1..100)]); # _Robert Israel_, Jan 27 2021
%t okQ[n_] := !PrimeQ[n-2^(Length[IntegerDigits[n, 2]]-1)];
%t Select[Prime[Range[100]], okQ] (* _Jean-François Alcover_, Feb 04 2023 *)
%Y Cf. A118957, A091932, A156695.
%Y Cf. A049084, A065381, A118953.
%K nonn
%O 1,1
%A _Reinhard Zumkeller_, May 07 2006
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