A265990 Number of nX7 integer arrays with each element equal to the number of horizontal and antidiagonal neighbors not equal to itself.

1, 7, 9, 24, 59, 137, 422, 865, 2777, 5666, 16753, 35213, 94722, 205921, 510225, 1143426, 2648225, 6090517, 13350146, 31380721, 65741593, 157403330, 317579601, 772359709, 1509772802, 3721329089, 7080934945, 17656526082, 32827306561

Offset

1,2

Comments

Column 7 of A265991.

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = a(n-1) +16*a(n-2) -15*a(n-3) -97*a(n-4) +84*a(n-5) +268*a(n-6) -208*a(n-7) -304*a(n-8) +192*a(n-9) +64*a(n-10) for n>15

Example

Some solutions for n=4
..1..3..1..1..3..1..1....1..3..1..1..3..1..1....1..3..2..2..1..1..2
..1..1..1..1..1..4..2....2..1..1..1..1..4..2....2..3..3..1..1..3..1
..2..4..1..1..1..1..1....1..4..1..1..3..3..2....1..1..1..1..3..1..1
..1..1..3..1..1..3..1....2..1..1..2..2..3..1....1..3..1..1..1..3..1

Crossrefs

Cf. A265991.

Sequence in context: A029633 A049301 A102028 * A125260 A192859 A104703

Adjacent sequences: A265987 A265988 A265989 * A265991 A265992 A265993

Keyword

nonn

Author

R. H. Hardin, Dec 19 2015

Status

approved