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A221023 Equals one maps: number of n X 5 binary arrays indicating the locations of corresponding elements equal to exactly one of their horizontal, vertical and antidiagonal neighbors in a random 0..3 n X 5 array. 1
16, 726, 30167, 1038208, 33512960, 1073575936, 34359074816, 1099508973568, 35184361472000, 1125899864375296, 36028796849094656, 1152921503927369728, 36893488144701194240, 1180591620706539667456, 37778931862913675165696 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A221024.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..39

FORMULA

Empirical: a(n) = 36*a(n-1) - 128*a(n-2) for n>5.

Empirical g.f.: x*(16 + 150*x + 6079*x^2 + 45124*x^3 - 1152*x^4) / ((1 - 4*x)*(1 - 32*x)). - Colin Barker, Aug 03 2018

EXAMPLE

Some solutions for n=3:

..1..0..0..0..1....1..0..0..1..0....0..1..1..0..1....1..0..1..0..0

..0..1..1..0..0....1..0..0..0..1....1..0..1..1..0....0..0..1..0..1

..0..1..0..1..0....1..1..1..1..0....0..1..1..0..0....1..0..1..0..0

CROSSREFS

Cf. A221024.

Sequence in context: A264114 A201622 A220809 * A171736 A062206 A209537

Adjacent sequences:  A221020 A221021 A221022 * A221024 A221025 A221026

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 28 2012

STATUS

approved

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Last modified December 4 05:52 EST 2021. Contains 349470 sequences. (Running on oeis4.)