A302467 Number of nX3 0..1 arrays with every element equal to 1, 2, 3 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

1, 14, 49, 250, 1147, 5486, 25599, 121626, 572657, 2702270, 12758927, 60200726, 284075917, 1340774674, 6327058239, 29858586774, 140911377557, 664983975698, 3138197357535, 14809850612998, 69890644606749, 329828551233330

Offset

1,2

Comments

Column 3 of A302472.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +9*a(n-2) +15*a(n-3) -68*a(n-4) -132*a(n-5) +96*a(n-6) +136*a(n-7) -34*a(n-8) -276*a(n-9) +188*a(n-10) -8*a(n-11) +32*a(n-12) -16*a(n-13) +64*a(n-14)

Example

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

Crossrefs

Cf. A302472.

Sequence in context: A308834 A084049 A251221 * A303249 A215569 A246973

Adjacent sequences: A302464 A302465 A302466 * A302468 A302469 A302470

Keyword

nonn

Author

R. H. Hardin, Apr 08 2018

Status

approved