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 A214517 #4 Aug 06 2012 18:45:31 %S A214517 1,1,2,2,1,2,2,1,5,2,7,1,5,4,5,3,2,8,3,2,2,1,2,2,6,2,3,2,5,3,2,2,10,1, %T A214517 2,7,3,3,2,5,3,2,2,3,5,2,8,3,4,6,7,5,17,1,5,2,3,7,5,3,2,2,10,1,2,2,8, %U A214517 3,20,4,6,7,3,4,5,20,1,4,1,4,10,3,3,2,3 %N A214517 Differences between the numbers n such that 4n^2 + 1 is prime. %C A214517 Sequence A001912 has the values of n. This sequence is the first differences of A001912. %H A214517 T. D. Noe, <a href="/A214517/b214517.txt">Table of n, a(n) for n = 1..10000</a> %F A214517 a(n) = A214516(n)/2 for n > 1. %t A214517 Differences[Select[Range[100], PrimeQ[1 + 4*#^2] &, 101]] %Y A214517 Cf. A121326 (primes of the form 1+4*n^2), A001912 (values of n). %K A214517 nonn %O A214517 1,3 %A A214517 _T. D. Noe_, Aug 06 2012