login
A316119
Number of nX4 0..1 arrays with every element unequal to 0, 2, 3, 5, 6 or 7 king-move adjacent elements, with upper left element zero.
1
1, 13, 23, 56, 213, 702, 2524, 9034, 33185, 120129, 440997, 1617873, 5923243, 21727149, 79684290, 292246407, 1071890143, 3931760361, 14421679034, 52899023769, 194038043140, 711745909568, 2610741818016, 9576434659125
OFFSET
1,2
COMMENTS
Column 4 of A316123.
FORMULA
Empirical recurrence of order 70 (see link above)
EXAMPLE
Some solutions for n=5
..0..1..1..0. .0..0..0..1. .0..1..1..1. .0..0..0..1. .0..0..0..0
..1..0..1..0. .1..1..0..0. .1..0..0..0. .1..1..1..0. .1..1..1..1
..1..0..0..0. .1..0..1..0. .0..1..1..0. .1..0..0..0. .1..0..0..1
..0..1..1..0. .0..0..1..0. .1..0..0..1. .1..0..1..0. .1..0..0..1
..1..0..0..1. .1..1..0..1. .0..1..1..0. .0..1..1..0. .1..0..0..1
CROSSREFS
Cf. A316123.
Sequence in context: A194156 A139863 A304672 * A046862 A155093 A147443
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jun 24 2018
STATUS
approved