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%I #9 Aug 13 2023 09:32:49
%S 1,2,3,5,8,9,11,23,29,41,53,81,83,89,113,125,128,131,173,179,191,233,
%T 239,243,251,281,293,359,419,431,443,491,509,593,641,653,659,683,719,
%U 729,743,761,809,911,953,1013,1019,1031,1049,1103,1223,1229,1289,1331,1409,1439,1451,1481,1499
%N Prime powers (A000961) q such that 2*q+1 is a prime.
%H Jianing Song, <a href="/A364926/b364926.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = (A048184(n)-1)/2.
%e 9 is a term since 9 = 3^2 and that 2*9+1 = 19 is prime.
%o (PARI) is(n) = (n==1) || (isprimepower(n) && isprime(2*n+1))
%Y {2*a(n)+1} gives A048184.
%Y Supersequence of A005384.
%Y Cf. A000961.
%K nonn,easy
%O 1,2
%A _Jianing Song_, Aug 13 2023