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%I #16 Feb 16 2021 00:58:30
%S 31,37,67,73,97,127,157,199,229,241,277,283,307,313,331,337,367,379,
%T 397,409,457,487,499,547,577,607,619,643,661,727,757,769,787,823,829,
%U 877,907,937,967,997,1039,1087,1117,1123,1237,1249,1291,1297,1327,1447
%N Primes p such that sigma(2*p+1) > 3*(p+1).
%C Equivalently sequence gives primes in A053224(k)/2 when A053224(k) is even.
%o (PARI) isok(p) = isprime(p) && (sigma(2*p+1) > 3*(p+1)); \\ _Michel Marcus_, Nov 23 2013
%Y Cf. A053224.
%K nonn
%O 1,1
%A _Benoit Cloitre_, Feb 08 2002
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