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A301356
Number of nX3 0..1 arrays with every element equal to 1, 2, 4, 5 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
1
1, 6, 13, 34, 92, 256, 721, 2036, 5701, 15848, 43916, 121825, 338722, 943311, 2628900, 7326706, 20413096, 56853677, 158313447, 440815860, 1227496584, 3418358547, 9520049340, 26513664655, 73841105634, 205645969535, 572712412815
OFFSET
1,2
COMMENTS
Column 3 of A301361.
LINKS
FORMULA
Empirical: a(n) = 8*a(n-1) -26*a(n-2) +47*a(n-3) -60*a(n-4) +74*a(n-5) -85*a(n-6) +71*a(n-7) -68*a(n-8) +56*a(n-9) -10*a(n-10) +72*a(n-11) -8*a(n-12) -148*a(n-13) -108*a(n-14) -6*a(n-15) +182*a(n-16) +168*a(n-17) +76*a(n-18) -38*a(n-19) -60*a(n-20) -64*a(n-21) -62*a(n-22) +49*a(n-24) +28*a(n-25) -10*a(n-26) -17*a(n-27) -2*a(n-28) +6*a(n-29) +a(n-30) -a(n-31)
EXAMPLE
Some solutions for n=5
..0..1..1. .0..0..0. .0..1..1. .0..0..0. .0..1..0. .0..0..1. .0..0..1
..0..0..1. .1..1..1. .0..0..1. .0..0..1. .0..1..0. .1..0..1. .0..1..0
..1..0..1. .0..0..0. .1..0..1. .0..1..1. .0..1..1. .1..0..0. .1..0..0
..1..0..1. .0..0..1. .1..0..1. .1..1..1. .0..0..0. .1..1..1. .0..0..0
..1..0..0. .0..1..1. .1..0..1. .0..0..0. .1..1..1. .0..0..0. .1..1..1
CROSSREFS
Cf. A301361.
Sequence in context: A041068 A300430 A300634 * A037243 A107710 A114689
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 19 2018
STATUS
approved