A316285 Number of nX4 0..1 arrays with every element unequal to 0, 1, 2, 3, 6 or 8 king-move adjacent elements, with upper left element zero.

8, 49, 125, 354, 1372, 3933, 12454, 42946, 135396, 437859, 1454625, 4718224, 15398305, 50682956, 165816368, 543317768, 1785073445, 5856614373, 19223124004, 63151760399, 207409161018, 681297182756, 2238603218152, 7355417198037

Offset

1,1

Comments

Column 4 of A316289.

Links

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

Formula

Empirical: a(n) = 7*a(n-1) -15*a(n-2) +22*a(n-3) -91*a(n-4) +194*a(n-5) -128*a(n-6) +198*a(n-7) -559*a(n-8) +288*a(n-9) +210*a(n-10) +102*a(n-11) -58*a(n-12) -534*a(n-13) +420*a(n-14) -139*a(n-15) +238*a(n-16) -200*a(n-17) +56*a(n-18) -24*a(n-19) +18*a(n-20) -4*a(n-21) for n>25

Example

Some solutions for n=5
..0..0..0..1. .0..1..1..0. .0..1..1..0. .0..0..0..0. .0..0..0..1
..0..0..0..1. .0..0..1..0. .0..0..1..0. .0..0..0..0. .0..0..1..1
..0..0..1..0. .0..0..0..0. .0..0..0..0. .0..1..1..0. .0..0..0..0
..0..0..0..1. .1..0..0..0. .0..0..0..0. .1..0..0..1. .0..1..0..0
..1..0..0..1. .1..1..0..0. .0..0..0..0. .1..1..1..1. .0..0..0..0

Crossrefs

Cf. A316289.

Sequence in context: A352179 A304468 A272713 * A018200 A306049 A317226

Adjacent sequences: A316282 A316283 A316284 * A316286 A316287 A316288

Keyword

nonn

Author

R. H. Hardin, Jun 28 2018

Status

approved