A268885 Number of nX7 binary arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once.

38, 1340, 42362, 1187838, 31427480, 800733668, 19876401224, 483987898760, 11611969197776, 275345016177616, 6466964539799840, 150689548401385312, 3487912674084234304, 80273121207141357120, 1838370376874099584640

Offset

1,1

Comments

Column 7 of A268886.

Links

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

Formula

Empirical: a(n) = 68*a(n-1) -1804*a(n-2) +24560*a(n-3) -195400*a(n-4) +974752*a(n-5) -3171360*a(n-6) +6871936*a(n-7) -9999248*a(n-8) +9740096*a(n-9) -6250176*a(n-10) +2552576*a(n-11) -621824*a(n-12) +79872*a(n-13) -4096*a(n-14) for n>16

Example

Some solutions for n=3
..1..0..0..0..0..0..0. .0..0..0..1..0..1..0. .0..0..0..1..0..1..1
..0..1..1..0..0..0..0. .1..1..0..1..0..1..0. .1..0..0..0..0..0..0
..0..0..0..1..0..0..1. .0..1..0..0..0..0..0. .0..0..0..0..0..0..0

Crossrefs

Cf. A268886.

Sequence in context: A239043 A137030 A027657 * A162858 A163221 A163660

Adjacent sequences: A268882 A268883 A268884 * A268886 A268887 A268888

Keyword

nonn

Author

R. H. Hardin, Feb 15 2016

Status

approved