

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
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OFFSET

1,1


COMMENTS

Column 3 of A302877.


LINKS

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


FORMULA

Empirical: a(n) = 3*a(n1) +9*a(n3) 15*a(n4) 5*a(n5) 22*a(n6) 7*a(n7) +9*a(n8) 32*a(n9) 10*a(n10) 16*a(n11) 40*a(n12) 16*a(n13) 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
Adjacent sequences: A302869 A302870 A302871 * A302873 A302874 A302875


KEYWORD

nonn


AUTHOR

R. H. Hardin, Apr 15 2018


STATUS

approved



