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%I #15 Jan 24 2024 08:30:15
%S 2,3,7,11,13,23,37,47,59,61,73,83,107,157,167,179,193,227,263,277,313,
%T 347,359,383,397,421,457,467,479,503,541,563,587,613,661,673,719,733,
%U 757,839,863,877,887,983,997,1019,1093,1153,1187,1201,1213,1237,1283
%N Primes which are not the sum of two consecutive nonprimes A141468.
%C 2, and primes p such that floor(p/2) or ceiling(p/2) is prime, but not both. - _Robert Israel_, Jan 23 2024
%H Robert Israel, <a href="/A167609/b167609.txt">Table of n, a(n) for n = 1..10000</a>
%p filter:= proc(n) if n mod 4 = 1
%p then isprime(n) and isprime((n+1)/2)
%p else isprime(n) and isprime((n-1)/2)
%p fi end proc:
%p 2, 3, op(select(filter, [seq(i,i=7 .. 10000, 2)])); # _Robert Israel_, Jan 23 2024
%Y Cf. A000040, A005383, A005385, A060254, A079149, A141468.
%K nonn
%O 1,1
%A _Juri-Stepan Gerasimov_, Nov 07 2009
%E Entries checked by _R. J. Mathar_, May 30 2010