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 A033102 #7 Nov 15 2012 04:26:57
%S A033102 0,0,0,1,1,1,1,1,2,3,4,5,6,8,9,11,12,14,16,19,21,25,27,32,35,38,40,46,
%T A033102 50,53,56,61,64,71,73,78,82,86,91,98,101,105,109,117,121,129,133,140,
%U A033102 148,152,155,164,169,176,180,186,190,198,204
%N A033102 Number of 4's when k is written in base b for all b and k satisfying 2<=b<=n+1, 1<=k<=n.
%t A033102 f[n_] := Count[ Flatten@ Table[ IntegerDigits[k, b], {k, n}, {b, 2, n + 1}], 4] - (n - 4); f[1] = f[2] = f[3] = 0; Array[f, 59] (* _Robert G. Wilson v_, Nov 14 2012 *)
%Y A033102 Cf. A033094, A033096, A033098, A033100, A033101, A033104, A033106, A033108, A033110, A033112.
%K A033102 nonn,base
%O A033102 1,9
%A A033102 _Clark Kimberling_