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A268969
Number of n X 6 0..2 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two not more than once.
1
336, 11664, 339480, 9093528, 231730344, 5712070032, 137497776840, 3251386055664, 75828095546544, 1748970953035272, 39976056137974824, 906854671261865016, 20440902679961179824, 458229741557275128024
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 50*a(n-1) - 805*a(n-2) + 4662*a(n-3) - 12150*a(n-4) + 14580*a(n- 5) -6561*a(n-6).
Empirical g.f.: 24*x*(14 - 214*x + 1115*x^2 - 2391*x^3 + 1674*x^4 + 243*x^5) / (1 - 25*x + 90*x^2 - 81*x^3)^2. - Colin Barker, Jan 17 2019
EXAMPLE
Some solutions for n=2:
..1..0..0..0..1..2. .1..2..2..0..1..2. .0..0..1..2..2..2. .1..0..1..0..0..0
..0..1..0..0..1..1. .1..2..1..2..2..2. .0..1..2..2..2..2. .1..0..0..0..0..0
CROSSREFS
Column 6 of A268971.
Sequence in context: A229697 A268626 A258418 * A056933 A289346 A386817
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 16 2016
STATUS
approved