A297715 Number of nX3 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1, 2 or 4 neighboring 1s.

4, 34, 145, 747, 4090, 21116, 110551, 582755, 3055652, 16036278, 84225551, 442157803, 2321279598, 12187515422, 63986012963, 335934438957, 1763713210610, 9259764998068, 48615161059469, 255237152397199, 1340034403055100

Offset

1,1

Comments

Column 3 of A297720.

Links

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

Formula

Empirical: a(n) = a(n-1) +8*a(n-2) +64*a(n-3) +85*a(n-4) +19*a(n-5) -569*a(n-6) -1161*a(n-7) -1173*a(n-8) +125*a(n-9) +1720*a(n-10) +1802*a(n-11) +1328*a(n-12) +240*a(n-13)

Example

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

Crossrefs

Cf. A297720.

Sequence in context: A054464 A002101 A241231 * A129557 A231518 A196908

Adjacent sequences: A297712 A297713 A297714 * A297716 A297717 A297718

Keyword

nonn

Author

R. H. Hardin, Jan 04 2018

Status

approved