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 A293959 #13 Nov 05 2017 19:25:29
%S A293959 0,0,1,0,0,1,2,0,0,0,1,0,1,2,3,0,0,0,0,1,0,0,1,0,1,2,0,1,2,3,4,0,0,0,
%T A293959 0,0,1,0,0,0,1,0,0,1,0,1,2,0,0,1,0,1,2,0,1,2,3,0,1,2,3,4,5,0,0,0,0,0,
%U A293959 0,1,0,0,0,0,1,0,0,0,1,0,0,1,0,1,2,0,0,0,1,0,0,1,0,1,2,0,0,1,0,1,2,0,1,2,3,0,0,1,0,1,2,0,1,2,3,0,1,2,3,4
%N A293959 Construct a triangle T(n,k) (0 <= k <= n) of strings of integers, where T(0,0) = {0}, T(n,n) = {n}, and otherwise T(n,k) is the concatenation of T(n-1,k-1) and T(n-1,k). The sequence is obtained by reading across the rows of the triangle, concatenating the successive strings.
%C A293959 The string T(n,k) contains binomial(n,k) numbers.
%e A293959 The first few rows of the triangle (where the strings T(n,k) are shown without spaces for legibility) are:
%e A293959 0,
%e A293959 0,1,
%e A293959 0,01,2,
%e A293959 0,001,012,3,
%e A293959 0,0001,001012,0123,4,
%e A293959 0,00001,0001001012,0010120123,01234,5,
%e A293959 ...
%Y A293959 Subtracting 1 from each term gives A265754.
%Y A293959 Cf. A007318.
%K A293959 nonn,tabf
%O A293959 0,7
%A A293959 _N. J. A. Sloane_, Nov 05 2017