A296573 Number of nX3 0..1 arrays with each 1 horizontally, vertically or antidiagonally adjacent to 0, 1 or 3 neighboring 1s.

7, 31, 135, 616, 2782, 12544, 56646, 255699, 1154239, 5210459, 23520746, 106176061, 479294501, 2163605794, 9766834956, 44088930859, 199023922776, 898423280994, 4055614926483, 18307642707131, 82643393810855, 373064443621418

Offset

1,1

Comments

Column 3 of A296578.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +9*a(n-2) +11*a(n-3) -2*a(n-4) -a(n-5) +10*a(n-6) +2*a(n-7) -29*a(n-8) -16*a(n-9) +27*a(n-10) +7*a(n-11) -12*a(n-12) -a(n-13) +2*a(n-14)

Example

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

Crossrefs

Cf. A296578.

Sequence in context: A001896 A262630 A282857 * A180147 A044049 A255284

Adjacent sequences: A296570 A296571 A296572 * A296574 A296575 A296576

Keyword

nonn

Author

R. H. Hardin, Dec 15 2017

Status

approved