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 A079030 #6 Mar 30 2012 18:39:12 %S A079030 1,5,11,14,47,26,71,41,59,74,167,89,191,101,131,146,383,236,311,194, %T A079030 251,269,647,299,479,314,419,341,887,461,719,446,659,614,1031,626, %U A079030 1487,1199,1019,689,1151,794,1847,854,971,941,3023,1106,1511,1109,1091,1256,2711 %N A079030 Least k such that the class number of quadratic order of discriminant D=-4k equals n. %o A079030 (PARI) a(n)=if(n<0,0,k=1; while(abs(n-qfbclassno(-4*k))>0,k++); k) %Y A079030 Cf. A000003. %K A079030 nonn %O A079030 1,2 %A A079030 _Benoit Cloitre_, Feb 01 2003