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 A138028 #5 Apr 20 2013 04:52:32
%S A138028 1,1,1,1,2,1,1,3,4,1,1,4,9,8,1,1,5,1,2,1,1,1,6,2,6,8,3,1,1,7,3,1,2,2,
%T A138028 6,1,1,8,4,2,6,1,7,1,1,1,9,6,3,1,3,4,2,2,1,1,1,8,5,2,7,1,1,6,5,1,1,1,
%U A138028 1,7,4,1,4,7,6,1,1,1,1,1,1,1,6,3,1,2,3,2,5,2,1,1,1,1,1,1,5,2,8,1,1,1,1,4,1
%N A138028 The array of the most significant digit of n^k read by antidiagonals.
%e A138028 n\k
%e A138028 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, ... .
%e A138028 1, 2, 4, 8, 1, 3, 6, 1, 2, 5, 1, 2, 4, 8, 1, 3, 6, 1, 2, 5, 1, ... .
%e A138028 1, 3, 9, 2, 8, 2, 7, 2, 6, 1, 5, 1, 5, 1, 4, 1, 4, 1, 3, 1, 3, ... .
%e A138028 1, 4, 1, 6, 2, 1, 4, 1, 6, 2, 1, 4, 1, 6, 2, 1, 4, 1, 6, 2, 1, ... .
%e A138028 1, 5, 2, 1, 6, 3, 1, 7, 3, 1, 9, 4, 2, 1, 6, 3, 1, 7, 3, 1, 9, ... .
%e A138028 1, 6, 3, 2, 1, 7, 4, 2, 1, 1, 6, 3, 2, 1, 7, 4, 2, 1, 1, 6, 3, ... .
%e A138028 1, 8, 6, 5, 4, 3, 2, 2, 1, 1, 1, 8, 6, 5, 4, 3, 2, 2, 1, 1, 1, ... .
%e A138028 1, 9, 8, 7, 6, 5, 5, 4, 4, 3, 3, 3, 2, 2, 2, 2, 1, 1, 1, 1, 1, ... .
%e A138028 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, ... .
%e A138028 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 4, 4, 5, 5, 6, 6, ... .
%e A138028 1, 1, 1, 1, 2, 2, 2, 3, 4, 5, 6, 7, 8, 1, 1, 1, 1, 2, 2, 3, 3, ... .
%e A138028 ......................................................................
%t A138028 f[n_, k_] := Quotient[n^k, 10^Floor[k*Log[10, n]]]; Table[f[ n - k, k], {n, 14}, {k, 0, n - 1}] // Flatten
%Y A138028 Cf. A008952, A060956, A138029, A061505.
%K A138028 base,nonn,tabl
%O A138028 1,5
%A A138028 _Robert G. Wilson v_, Feb 10 2008