A302455 Number of nX3 0..1 arrays with every element equal to 0, 2, 3 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

1, 11, 18, 55, 177, 474, 1397, 4135, 11882, 34847, 101857, 296482, 867237, 2532855, 7392050, 21600199, 63090609, 184246522, 538224973, 1572126423, 4591906058, 13413050687, 39179099921, 114439818402, 334276528661, 976412435063

Offset

1,2

Comments

Column 3 of A302460.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) -2*a(n-2) +13*a(n-3) -23*a(n-4) +12*a(n-5) -42*a(n-6) +32*a(n-7) -24*a(n-8) -18*a(n-9) +24*a(n-10) +40*a(n-11) +32*a(n-12)

Example

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

Crossrefs

Cf. A302460.

Sequence in context: A037006 A188892 A168433 * A303237 A066950 A352955

Adjacent sequences: A302452 A302453 A302454 * A302456 A302457 A302458

Keyword

nonn

Author

R. H. Hardin, Apr 08 2018

Status

approved