A250560 Number of length n+2 0..7 arrays with the sum of second differences multiplied by some arrangement of +-1 equal to zero.

32, 480, 5446, 63400, 695890, 6924692, 62245658, 522997696, 4258085394, 34261234132, 274598186760, 2198154605100, 17589251301614, 140726940443068

Offset

1,1

Comments

Column 7 of A250561

Links

Table of n, a(n) for n=1..14.

Example

Some solutions for n=4
..1....5....5....0....4....2....3....6....6....3....2....6....6....3....7....7
..5....4....2....5....3....1....0....2....5....6....4....4....1....2....7....4
..1....3....0....7....3....0....6....4....3....0....5....4....7....5....2....2
..1....6....2....1....0....4....4....1....2....2....0....0....5....0....1....0
..1....7....0....5....2....5....6....4....3....3....3....6....4....1....2....5
..5....2....5....4....5....4....3....2....2....4....7....4....1....0....0....4

Crossrefs

Sequence in context: A000152 A319307 A022069 * A203720 A306411 A085539

Adjacent sequences: A250557 A250558 A250559 * A250561 A250562 A250563

Keyword

nonn

Author

R. H. Hardin, Nov 25 2014

Status

approved