[go: up one dir, main page]

login
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).
1
0, 0, 0, 1, 0, 0, 3, 16, 0, 0, 6, 78, 193, 0, 0, 10, 228, 1548, 2080, 0, 0, 15, 520, 6714, 27768, 21121, 0, 0, 21, 1020, 21280, 181032, 474288, 206896, 0, 0, 28, 1806, 55395, 807040, 4697166, 7888608, 1979713, 0, 0, 36, 2968, 125748, 2817240, 29708800
OFFSET
1,7
FORMULA
T(n, d) = (n^(2d) - (3n-2)^d) / 2 for n>0, d>0.
EXAMPLE
The table begins:
0 0 0 0 0 ...
0 0 0 0 0 ...
1 16 193 2080 21121 ...
3 78 1548 27768 474288 ...
6 228 6714 181032 4697166 ...
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.
The antidiagonals are read from southwest to northeast.
CROSSREFS
Cf. A000217(n-2) (T(n,1)).
Cf. A061995 (T(n,2)).
Cf. A166540 (T(n,3)).
Sequence in context: A364799 A004002 A216149 * A078355 A107823 A139815
KEYWORD
nonn,tabl
AUTHOR
Andrew Woods, Aug 30 2011
STATUS
approved