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A268903
Number of nX7 0..2 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once.
1
576, 34344, 1585800, 66210264, 2611960344, 99308573208, 3679171151832, 133712637011640, 4788143315276472, 169455769674019992, 5940079034652505944, 206577531186380751096, 7136252899974195705720, 245118805391945325271896
OFFSET
1,1
COMMENTS
Column 7 of A268904.
LINKS
FORMULA
Empirical: a(n) = 84*a(n-1) -2466*a(n-2) +31428*a(n-3) -206469*a(n-4) +750384*a(n-5) -1513404*a(n-6) +1574640*a(n-7) -656100*a(n-8)
EXAMPLE
Some solutions for n=2
..0..1..0..0..0..0..1. .1..0..1..0..0..0..1. .0..0..0..1..2..2..1
..2..2..1..0..1..2..1. .1..0..0..0..0..2..2. .1..1..2..2..1..2..2
CROSSREFS
Cf. A268904.
Sequence in context: A230522 A223301 A168660 * A373454 A249688 A079396
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 15 2016
STATUS
approved