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A268636
Number of nX5 0..2 arrays with some element plus some horizontally or vertically adjacent neighbor totalling two exactly once.
1
96, 1944, 29772, 412740, 5419992, 68710116, 849572724, 10310685036, 123340687488, 1458578214948, 17087534233740, 198629587902636, 2293776106412328, 26339884438238244, 300996939426028068
OFFSET
1,1
COMMENTS
Column 5 of A268639.
LINKS
FORMULA
Empirical: a(n) = 32*a(n-1) -386*a(n-2) +2264*a(n-3) -7265*a(n-4) +13512*a(n-5) -14960*a(n-6) +9872*a(n-7) -3776*a(n-8) +768*a(n-9) -64*a(n-10)
EXAMPLE
Some solutions for n=3
..1..2..2..2..1. .1..0..0..0..0. .0..1..2..2..2. .1..2..1..0..1
..0..1..0..1..2. .2..1..0..1..0. .1..2..2..2..1. .2..2..2..2..2
..1..0..1..2..1. .0..0..1..0..0. .1..2..2..2..2. .1..2..1..2..2
CROSSREFS
Cf. A268639.
Sequence in context: A001667 A093984 A159711 * A233153 A204624 A090449
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 09 2016
STATUS
approved