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A303237
Number of nX3 0..1 arrays with every element equal to 0, 2, 3, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
1
1, 11, 18, 55, 181, 494, 1465, 4415, 12934, 38423, 114145, 337914, 1003161, 2976083, 8824906, 26185191, 77678573, 230413110, 683562697, 2027805127, 6015399582, 17845009895, 52937661977, 157040038306, 465863595657, 1381994981979
OFFSET
1,2
COMMENTS
Column 3 of A303242.
LINKS
FORMULA
Empirical: a(n) = 4*a(n-1) -5*a(n-2) +16*a(n-3) -36*a(n-4) +32*a(n-5) -63*a(n-6) +64*a(n-7) -51*a(n-8) +4*a(n-9) +60*a(n-10) +16*a(n-11) +112*a(n-12) +64*a(n-13)
EXAMPLE
Some solutions for n=5
..0..0..1. .0..1..1. .0..1..0. .0..0..1. .0..0..0. .0..1..1. .0..1..1
..0..0..1. .1..1..0. .0..1..0. .0..0..1. .1..0..0. .0..1..1. .1..1..0
..1..0..0. .0..1..0. .0..1..0. .1..0..1. .1..0..1. .1..1..0. .0..1..1
..0..0..1. .1..1..1. .1..1..1. .0..0..0. .1..0..0. .0..1..1. .0..1..1
..0..0..1. .0..1..1. .0..1..1. .1..0..1. .1..0..0. .1..1..0. .0..1..1
CROSSREFS
Cf. A303242.
Sequence in context: A188892 A168433 A302455 * A066950 A352955 A214495
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 20 2018
STATUS
approved