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A268902 Number of n X 6 0..2 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once. 1
240, 9720, 299088, 8250912, 214142760, 5344944120, 129834259704, 3091414865040, 72488795124312, 1679265104747616, 38520989302343760, 876481043382776664, 19806871824479466648, 444994736265664134120, 9947337685046673808176 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

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*(10 - 95*x + 262*x^2 + 93*x^3 - 1485*x^4 + 1701*x^5) / (1 - 25*x + 90*x^2 - 81*x^3)^2. - Colin Barker, Jan 16 2019

EXAMPLE

Some solutions for n=2:

..0..0..0..0..0..0. .1..2..2..2..1..2. .2..2..2..2..2..2. .2..1..2..2..2..2

..0..1..0..1..1..2. .1..0..1..2..1..0. .2..1..1..2..1..0. .2..2..1..0..1..2

CROSSREFS

Column 6 of A268904.

Sequence in context: A251434 A187167 A282227 * A232994 A023906 A292883

Adjacent sequences:  A268899 A268900 A268901 * A268903 A268904 A268905

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 15 2016

STATUS

approved

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Last modified August 19 18:30 EDT 2022. Contains 356229 sequences. (Running on oeis4.)