login
A302872
Number of nX3 0..1 arrays with every element equal to 0, 1, 3, 4 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
1
3, 11, 17, 37, 82, 209, 536, 1549, 4513, 13980, 44424, 142457, 463592, 1518144, 4985864, 16423493, 54170895, 178797985, 590488247, 1950654770, 6444889749, 21296082916, 70373480203, 232558689443, 768538881502, 2539828012418
OFFSET
1,1
COMMENTS
Column 3 of A302877.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) +9*a(n-3) -15*a(n-4) -5*a(n-5) -22*a(n-6) -7*a(n-7) +9*a(n-8) -32*a(n-9) -10*a(n-10) -16*a(n-11) -40*a(n-12) -16*a(n-13) for n>16
EXAMPLE
Some solutions for n=5
..0..0..1. .0..0..1. .0..0..1. .0..0..1. .0..1..0. .0..0..1. .0..0..0
..0..1..0. .1..1..1. .0..1..0. .1..1..1. .0..1..0. .1..1..1. .0..1..0
..0..1..0. .1..0..1. .0..1..0. .1..0..1. .0..1..0. .1..0..1. .0..1..0
..0..1..0. .1..0..0. .1..1..0. .1..0..1. .0..0..0. .1..0..1. .0..1..0
..0..0..0. .1..0..1. .0..1..0. .0..1..1. .0..1..1. .1..1..0. .0..1..0
CROSSREFS
Cf. A302877.
Sequence in context: A197225 A181507 A154934 * A023865 A024592 A203162
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 15 2018
STATUS
approved