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 A318597 #4 Aug 29 2018 17:18:59
%S A318597 1,1,17,327,6545,135751,2869719,61474519,1329890705,28987537806,
%T A318597 635627275767,14005614014756,309847743790935,6878045467021470,
%U A318597 153121753939078375,3417374882384868702,76435265515004093841,1712879663609111933495,38450113512250685307822
%N A318597 Number of n-member subsets of [9*n] whose elements sum to a multiple of nine.
%H A318597 Alois P. Heinz, <a href="/A318597/b318597.txt">Table of n, a(n) for n = 0..735</a>
%e A318597 a(2) = 17: {1,8}, {1,17}, {2,7}, {2,16}, {3,6}, {3,15}, {4,5}, {4,14}, {5,13}, {6,12}, {7,11}, {8,10}, {9,18}, {10,17}, {11,16}, {12,15}, {13,14}.
%Y A318597 Column k=9 of A318557.
%K A318597 nonn
%O A318597 0,3
%A A318597 _Alois P. Heinz_, Aug 29 2018