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 A194604 #12 Jul 21 2017 00:34:14 %S A194604 0,0,0,1,0,0,3,16,0,0,6,78,193,0,0,10,228,1548,2080,0,0,15,520,6714, %T A194604 27768,21121,0,0,21,1020,21280,181032,474288,206896,0,0,28,1806,55395, %U A194604 807040,4697166,7888608,1979713,0,0,36,2968,125748,2817240,29708800 %N A194604 Square table T(n, d) read by antidiagonals: number of ways to place 2 nonattacking kings on an n^d (n X n X ...) raumschach board (hypercubical chessboard). %F A194604 T(n, d) = (n^(2d) - (3n-2)^d) / 2 for n>0, d>0. %e A194604 The table begins: %e A194604 0 0 0 0 0 ... %e A194604 0 0 0 0 0 ... %e A194604 1 16 193 2080 21121 ... %e A194604 3 78 1548 27768 474288 ... %e A194604 6 228 6714 181032 4697166 ... %e A194604 There are T(3, 4) = 2080 ways to place 2 nonattacking kings on a 3^4 (3 X 3 X 3 X 3) hypercubical chessboard. %e A194604 The antidiagonals are read from southwest to northeast. %Y A194604 Cf. A000217(n-2) (T(n,1)). %Y A194604 Cf. A061995 (T(n,2)). %Y A194604 Cf. A166540 (T(n,3)). %K A194604 nonn,tabl %O A194604 1,7 %A A194604 _Andrew Woods_, Aug 30 2011