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%I #25 Sep 08 2022 08:46:16
%S 73,181,2341,4861,6121,9901,12601,18973,20161,26641,47701,51481,59473,
%T 61561,68041,79561,81973,84421,94573,110881,157321,185401,192781,
%U 207973,231841,244261,248473,270073,292573,335341,365473,440821,446473,452161,475273
%N Primes p such that 2*p + 79 is a square.
%C Primes of the form 2*k^2 + 2*k - 39.
%C 2*p + h is not verified if h is an odd prime that belongs to A055025 because (2*h-1)/2 is a multiple of 2.
%e a(1) = 73 because 2*73 + 79 = 225, which is a square.
%t Select[Prime[Range[50000]], IntegerQ[Sqrt[2 # + 79]] &]
%o (Magma) [p: p in PrimesUpTo(600000) | IsSquare(2*p+79)];
%o (PARI) lista(nn) = {forprime(p=2, nn, if(issquare(2*p + 79), print1(p, ", "))); } \\ _Altug Alkan_, Mar 24 2016
%o (Python)
%o from sympy import isprime
%o from gmpy2 import is_square
%o for p in range(0,1000000):
%o if(is_square(2*p+79) and isprime(p)):print(p)
%o # _Soumil Mandal_, Apr 03 2016
%Y Cf. A000040.
%Y Subsequence of A002144, A045433, A061237, A068228.
%Y Cf. similar sequences listed in A269784.
%K nonn
%O 1,1
%A _Vincenzo Librandi_, Mar 24 2016
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