A302159 Number of nX4 0..1 arrays with every element equal to 0, 1 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

5, 17, 12, 29, 73, 156, 361, 865, 1970, 4530, 10571, 24394, 56204, 130230, 301221, 695541, 1608549, 3720177, 8597848, 19876759, 45959426, 106246321, 245619039, 567865144, 1312830532, 3035049693, 7016724012, 16221856134, 37502724170

Offset

1,1

Comments

Column 4 of A302163.

Links

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

Formula

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

Example

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

Crossrefs

Cf. A302163.

Sequence in context: A180024 A356403 A178197 * A070848 A213738 A060829

Adjacent sequences: A302156 A302157 A302158 * A302160 A302161 A302162

Keyword

nonn

Author

R. H. Hardin, Apr 02 2018

Status

approved