A301349 Number of nX3 0..1 arrays with every element equal to 1, 2, 3, 5 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

1, 10, 53, 277, 1433, 7522, 39390, 206370, 1081141, 5664201, 29675091, 155470142, 814520042, 4267334800, 22356902816, 117129577486, 613651093697, 3214966486924, 16843463025482, 88244231458054, 462318489581630

Offset

1,2

Comments

Column 3 of A301354.

Links

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

Formula

Empirical: a(n) = 5*a(n-1) +5*a(n-2) -19*a(n-3) -6*a(n-4) +14*a(n-5) -3*a(n-6) +16*a(n-7) +19*a(n-8) -59*a(n-9) -41*a(n-10) +29*a(n-11) +8*a(n-12) +24*a(n-13) +51*a(n-14) -6*a(n-15) -32*a(n-16) -4*a(n-17) +4*a(n-18) for n>20

Example

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

Crossrefs

Cf. A301354.

Sequence in context: A300422 A300684 A300607 * A007035 A093187 A208616

Adjacent sequences: A301346 A301347 A301348 * A301350 A301351 A301352

Keyword

nonn

Author

R. H. Hardin, Mar 19 2018

Status

approved