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.
%I A204921 #8 Sep 20 2018 00:30:05 %S A204921 5,8,7,4,1,4,3,2,5,4,15,2,9,8,3,1,21,4,15,2,1,12,24,1,21,12,31,4,33,4, %T A204921 27,3,5,12,8,2,24,24,3,1,45,4,39,6,1,12,24,2,45,12,7,6,24,8,3,2,5,24, %U A204921 63,2 %N A204921 a(n) = (p(n)^2 - q(n)^2)/n, where (p(n)^2, q(n)^2) is the least pair of squared primes (ordered as at A204914) for which n divides p(n)^2 - q(n)^2. %C A204921 For a guide to related sequences, see A204892. %t A204921 (See the program at A204900.) %Y A204921 Cf. A204900, A204892. %K A204921 nonn %O A204921 1,1 %A A204921 _Clark Kimberling_, Jan 20 2012