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A282879 Number of nX2 0..1 arrays with no 1 equal to more than one of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly one element. 1
0, 2, 8, 32, 122, 416, 1414, 4626, 14930, 47432, 149032, 463918, 1432956, 4397436, 13419434, 40754026, 123245234, 371322718, 1115052844, 3338521720, 9969125698, 29697147320, 88271949298, 261856896380, 775373941754, 2292071140404 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Column 2 of A282885.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +7*a(n-2) -2*a(n-3) -20*a(n-4) -24*a(n-5) -19*a(n-6) -14*a(n-7) -7*a(n-8) -2*a(n-9) -a(n-10).
Empirical: G.f.: 2*x^2*(2*x+1)*(x^3+x^2+1) / ( (x^5+x^4+3*x^3+4*x^2+x-1)^2 ). - R. J. Mathar, Mar 02 2017
EXAMPLE
Some solutions for n=4
..0..0. .1..0. .1..0. .1..1. .0..1. .1..0. .1..1. .1..1. .1..0. .0..0
..0..0. .0..1. .0..0. .0..0. .0..1. .1..1. .0..1. .0..1. .0..1. .1..0
..1..1. .1..0. .1..1. .1..1. .1..0. .0..0. .0..0. .0..0. .0..1. .1..0
..0..1. .1..0. .0..1. .0..1. .0..1. .0..0. .1..1. .0..0. .0..1. .1..0
CROSSREFS
Cf. A282885.
Sequence in context: A099752 A230393 A230529 * A217665 A337863 A324568
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 24 2017
STATUS
approved

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Last modified July 21 21:26 EDT 2024. Contains 374475 sequences. (Running on oeis4.)