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 A091731 #11 Mar 21 2023 09:18:16 %S A091731 0,0,0,0,1,1,2,0,0,3,0,0,0,0,2,0,0,0,0,0,0,4,0,0,0,0,0,0,0,2,0,0,0,0, %T A091731 0,0,0,0,0,0,0,2,0,0,0,0,2,0,0,3,0,0,0,0,0,0,0,0,0,0,0,2 %N A091731 Number of irreducible elements of Z[sqrt(-5)] of norm n (counting a and -a once only). %D A091731 David A. Cox, Primes of the form x^2+ny^2, Wiley, 1989. %D A091731 A. Frohlich and M. J. Taylor, Algebraic number theory, Cambridge university press, 1991. %F A091731 See A091730. %K A091731 nonn,more %O A091731 0,7 %A A091731 _Paul Boddington_, Feb 02 2004