A300534 Number of nX3 0..1 arrays with every element equal to 0, 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

1, 5, 12, 36, 122, 429, 1585, 5755, 21084, 77823, 286982, 1060139, 3917406, 14477542, 53517820, 197837108, 731366681, 2703796615, 9995728589, 36953720967, 136616452365, 505066168745, 1867213688572, 6903032086068, 25520304669843

Offset

1,2

Comments

Column 3 of A300539.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +7*a(n-2) +6*a(n-3) -21*a(n-4) -36*a(n-5) -26*a(n-6) +4*a(n-7) +62*a(n-8) +82*a(n-9) +18*a(n-10) -52*a(n-11) -42*a(n-12) +72*a(n-13) +38*a(n-14) +12*a(n-15) -25*a(n-16) -16*a(n-17) -4*a(n-18) -6*a(n-19) +8*a(n-20) -4*a(n-21) +2*a(n-22) for n>24

Example

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

Crossrefs

Cf. A300539.

Sequence in context: A301873 A368094 A077918 * A359189 A297909 A220705

Adjacent sequences: A300531 A300532 A300533 * A300535 A300536 A300537

Keyword

nonn

Author

R. H. Hardin, Mar 08 2018

Status

approved