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 A137197 #19 Jul 05 2025 09:59:29 %S A137197 1,0,9,2,3,6,3,7,9,1,0,9,5,1,2,2,7,8,8,8,0,1,3,8,0,4,2,4,4,8,9,0,9,7, %T A137197 0,5,8,8,7,1,5,0,4,6,4,4,7,1,0,8,1,4,2,4,4,2,3,8,0,5,4,9,7,5,5,0,2,2, %U A137197 7,2,8,4,7,3,0,1,8,8,5,5,4,8,5,9,2,0,6,0,3,6,5,9,4,6,6,2,2,8,1,3,0 %N A137197 Decimal expansion of the sum of the reciprocals of the elements of A007908. %e A137197 1 + 1/12 + 1/123 + 1/1234 + 1/12345 + 1/123456 + .....= 1.0923637910951227888013796063072721016963921894258793349801635199721622546190953748287037568512919456 %p A137197 > readlib(log10); P:=proc(n) local a,i,j,k; a:=1; k:=2; j:=1; for i from 1 by 1 to n do j:=j*10^(trunc(evalf(log10(k)))+1)+k; a:=a+1/j; k:=k+1; lprint(evalf(a,101)); od; end: P(1000); %Y A137197 Cf. A007908. %K A137197 easy,nonn,base,cons %O A137197 1,3 %A A137197 _Paolo P. Lava_ and _Giorgio Balzarotti_, Mar 04 2008