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 A051816 #4 Jun 11 2014 17:24:22
%S A051816 1,7,58,422,2872,19772,142418,1096582,9040811,78452199,699839588,
%T A051816 6297456806,56804155533,517737762700,4839960759976,46837953974511
%N A051816 Number of n-digit numbers with nonzero multiplicative digital root 5.
%D A051816 William Mayne, sci.math, Jun 15 1991
%F A051816 # { i : 10^(n-1) < i < 10^n and A051802(i)=5 }
%Y A051816 Cf. A051802, A051807, A051825.
%K A051816 nonn,base,hard
%O A051816 1,2
%A A051816 _Dan Hoey_, Dec 09 1999