A301446 Number of nX4 0..1 arrays with every element equal to 0, 1, 2, 3, 5 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

8, 108, 1008, 9541, 91370, 877044, 8414314, 80726964, 774477323, 7430228709, 71284529536, 683893628760, 6561177596757, 62947000071013, 603904519316269, 5793773626269543, 55584635903151286, 533271050607294727

Offset

1,1

Comments

Column 4 of A301450.

Links

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

Formula

Empirical: a(n) = 9*a(n-1) +14*a(n-2) -82*a(n-3) +5*a(n-4) +210*a(n-5) -381*a(n-6) -224*a(n-7) -7*a(n-8) +790*a(n-9) +1112*a(n-10) -5103*a(n-11) +10610*a(n-12) +4283*a(n-13) -18136*a(n-14) +27908*a(n-15) -6641*a(n-16) -12938*a(n-17) +16505*a(n-18) -16973*a(n-19) -38570*a(n-20) +34834*a(n-21) -1406*a(n-22) -24627*a(n-23) +31869*a(n-24) +15063*a(n-25) -23509*a(n-26) +14505*a(n-27) +2202*a(n-28) -9988*a(n-29) -3801*a(n-30) +1439*a(n-31) -3136*a(n-32) +6064*a(n-33) -1559*a(n-34) -428*a(n-35) +1588*a(n-36) -1063*a(n-37) -352*a(n-38) +384*a(n-39) -64*a(n-40)

Example

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

Crossrefs

Cf. A301450.

Sequence in context: A300468 A326101 A300807 * A363476 A272497 A215129

Adjacent sequences: A301443 A301444 A301445 * A301447 A301448 A301449

Keyword

nonn

Author

R. H. Hardin, Mar 21 2018

Status

approved