

A282856


Number of nX2 0..1 arrays with no 1 equal to more than one of its horizontal, vertical and antidiagonal neighbors.


1



4, 11, 31, 89, 251, 715, 2028, 5761, 16358, 46452, 131910, 374581, 1063696, 3020560, 8577449, 24357268, 69167021, 196412696, 557750593, 1583837157, 4497601906, 12771782030, 36267864414, 102989386002, 292457628811, 830488149997
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OFFSET

1,1


COMMENTS

Column 2 of A282862.


LINKS

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


FORMULA

Empirical: a(n) = a(n1) +4*a(n2) +3*a(n3) +a(n4) +a(n5).
Empirical: G.f.: x*(1+x)*(x^3+x^2+3*x+4)/(1+x+4*x^2+3*x^3+x^4+x^5) .  R. J. Mathar, Mar 02 2017


EXAMPLE

Some solutions for n=4
..1..0. .0..1. .0..1. .0..0. .1..0. .1..1. .0..0. .0..1. .1..0. .0..0
..1..0. .1..0. .0..0. .1..0. .0..0. .0..0. .0..0. .1..0. .1..0. .0..0
..0..0. .0..0. .1..0. .1..0. .1..0. .1..0. .1..1. .0..1. .0..0. .1..0
..1..1. .1..1. .0..0. .0..0. .0..1. .0..1. .0..0. .0..0. .1..0. .0..1


CROSSREFS

Cf. A282862.
Sequence in context: A027115 A077995 A276293 * A296572 A176573 A134597
Adjacent sequences: A282853 A282854 A282855 * A282857 A282858 A282859


KEYWORD

nonn


AUTHOR

R. H. Hardin, Feb 23 2017


STATUS

approved



