cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A118941 Primes p such that (p^2-5)/4 is prime.

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%I A118941 #3 Mar 30 2012 17:22:42
%S A118941 5,7,11,13,17,19,23,31,41,43,53,61,71,79,83,89,97,101,107,109,113,131,
%T A118941 137,167,173,179,193,229,241,251,263,269,277,281,283,307,311,317,349,
%U A118941 353,373,383,419,431,439,461,463,467,563,571,577,593,607,613,619,647
%N A118941 Primes p such that (p^2-5)/4 is prime.
%C A118941 For all primes q>2, we have q=4k+-1 for some k, which makes it easy to show that 4 divides q^2-5. Similar sequences, with p and (p^2+a)/b both prime, are A048161, A062324, A062326, A062718, A109953, A110589, A118915, A118918, A118939, A118940 and A118942.
%t A118941 Select[Prime[Range[200]],PrimeQ[(#^2-5)/4]&]
%K A118941 nonn
%O A118941 1,1
%A A118941 _T. D. Noe_, May 06 2006