A302809 Number of 3Xn 0..1 arrays with every element equal to 0, 1, 2, 3 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

4, 32, 169, 934, 5117, 28128, 154494, 848519, 4660562, 25597855, 140595667, 772217905, 4241385457, 23295695745, 127950975583, 702767266506, 3859930159709, 21200561758854, 116443510741144, 639562826045595

Offset

1,1

Comments

Row 3 of A302808.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +14*a(n-2) +2*a(n-3) -22*a(n-4) +3*a(n-5) +37*a(n-6) -19*a(n-7) -4*a(n-8) +24*a(n-9) -4*a(n-10) +11*a(n-11) +8*a(n-12) +2*a(n-13) for n>15

Example

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

Crossrefs

Cf. A302808.

Sequence in context: A270076 A271149 A271201 * A303470 A222507 A270153

Adjacent sequences: A302806 A302807 A302808 * A302810 A302811 A302812

Keyword

nonn

Author

R. H. Hardin, Apr 13 2018

Status

approved