A297638 Number of 2Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 0, 2 or 3 neighboring 1s.

4, 8, 29, 69, 200, 552, 1641, 4685, 13716, 40248, 119365, 353541, 1051472, 3133592, 9358769, 27971501, 83684604, 250541896, 750515501, 2248981061, 6741211928, 20210867784, 60604323641, 181749073613, 545104106532, 1634992796824

Offset

1,1

Comments

Row 2 of A297637.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +a(n-2) -a(n-3) +6*a(n-4) -28*a(n-5) -24*a(n-6)

Example

Some solutions for n=7
..0..1..1..0..1..1..1. .1..0..1..1..1..0..0. .1..1..0..0..1..0..0
..1..1..0..0..1..1..0. .1..0..1..1..0..0..0. .1..1..1..1..1..1..0

Crossrefs

Cf. A297637.

Sequence in context: A300461 A280085 A322784 * A256456 A270522 A317583

Adjacent sequences: A297635 A297636 A297637 * A297639 A297640 A297641

Keyword

nonn

Author

R. H. Hardin, Jan 02 2018

Status

approved