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 A191355 #24 Apr 17 2023 06:17:12
%S A191355 5,6,8,9,12,15,18,22,27,31,37,43,49,56,64,71,80,89,98,108
%N A191355 Indices of terms in A069748 with two decimal digits 1 and all others 0.
%F A191355 Conjectural formula: a(n) = 5 + Sum_{i=1..n-1} A105637(i).
%F A191355 Equivalent conjecture: a(n) = -(-1)^n/8 + A049347(n)/3 + 115/24 + n/6 + n^2/4. - _R. J. Mathar_, Jul 11 2011
%Y A191355 Cf. A002780, A069748, A105637.
%K A191355 nonn,base,more
%O A191355 1,1
%A A191355 _Vladimir Shevelev_, May 31 2011
%E A191355 a(18)-a(20), using A002780 b-file, added by _Michel Marcus_, Apr 17 2023