A302310 Number of 2Xn 0..1 arrays with every element equal to 0, 1, 3 or 4 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

2, 3, 11, 21, 31, 113, 363, 813, 1751, 5001, 14051, 34053, 82063, 218273, 579291, 1452381, 3638471, 9447993, 24526163, 62318133, 158325631, 407598161, 1049289291, 2679681933, 6843284663, 17562012393, 45069368771, 115317418341

Offset

1,1

Comments

Row 2 of A302309.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) -a(n-2) +4*a(n-3) +12*a(n-4) -16*a(n-5) for n>6

Example

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

Crossrefs

Cf. A302309.

Sequence in context: A298351 A359017 A023182 * A295958 A049083 A305719

Adjacent sequences: A302307 A302308 A302309 * A302311 A302312 A302313

Keyword

nonn

Author

R. H. Hardin, Apr 05 2018

Status

approved