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 A076590 #14 Dec 30 2024 12:45:30
%S A076590 1,6,12,5,37,23,8,56,83,14,107,128,111,121,20,171,346,172,57,45,607,
%T A076590 641,968,925,239,291,44,659,396,233,186,1353,509,739,843,681,1020,213,
%U A076590 577,345,670,196,287,91,54,3510,910,800,3462,803,503,355,3428,1157,247
%N A076590 First occurrence of n as a term in the continued fraction for zeta(2)=Pi^2/6.
%t A076590 Module[{nn=4000,cf},cf=ContinuedFraction[Pi^2/6,nn];Table[Position[cf,n,1,1],{n,60}]]//Flatten (* _Harvey P. Dale_, Dec 29 2024 *)
%o A076590 (PARI) /* 15000 precision digits */ v=contfrac(zeta(2)); a(n)=if(n<0,0,s=1; while(abs(n-component(v,s))>0,s++); s)
%Y A076590 Cf. A013679, A032523.
%K A076590 base,nonn
%O A076590 1,2
%A A076590 _Benoit Cloitre_, Oct 20 2002