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A264791
Number of n X 1 arrays of permutations of 0..n*1-1 with rows nondecreasing modulo 2 and columns nondecreasing modulo 7.
6
1, 1, 1, 1, 1, 1, 1, 2, 4, 8, 16, 32, 64, 128, 384, 1152, 3456, 10368, 31104, 93312, 279936, 1119744, 4478976, 17915904, 71663616, 286654464, 1146617856, 4586471424, 22932357120, 114661785600, 573308928000, 2866544640000, 14332723200000, 71663616000000
OFFSET
1,8
COMMENTS
Column 1 of A264794.
LINKS
FORMULA
a(n) = Product_{i=0..6} floor((n+i)/7)!. - Alois P. Heinz, Jul 12 2016
a(n) ~ (2*Pi*n)^3 * n! / 7^(n + 7/2). - Vaclav Kotesovec, Oct 02 2018
EXAMPLE
All solutions for n=11
..0....0....7....0....7....0....7....7....7....7....0....0....0....7....0....7
..7....7....0....7....0....7....0....0....0....0....7....7....7....0....7....0
..1....1....8....8....8....1....1....8....1....8....8....8....8....1....1....1
..8....8....1....1....1....8....8....1....8....1....1....1....1....8....8....8
..9....2....2....9....9....2....9....2....2....9....9....2....2....9....9....2
..2....9....9....2....2....9....2....9....9....2....2....9....9....2....2....9
..3....3...10....3....3...10...10....3...10...10...10...10....3....3...10....3
.10...10....3...10...10....3....3...10....3....3....3....3...10...10....3...10
..4....4....4....4....4....4....4....4....4....4....4....4....4....4....4....4
..5....5....5....5....5....5....5....5....5....5....5....5....5....5....5....5
..6....6....6....6....6....6....6....6....6....6....6....6....6....6....6....6
MATHEMATICA
Table[Product[Floor[(n + i)/7]!, {i, 0, 6}], {n, 1, 40}] (* Vaclav Kotesovec, Oct 02 2018 *)
CROSSREFS
Cf. A264794.
Column k=7 of A275062.
Sequence in context: A275074 A290687 A290855 * A290851 A290670 A079838
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 25 2015
STATUS
approved