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A221189 Number of n X 2 arrays of occupancy after each element moves to some king-move neighbor. 2
1, 31, 318, 3605, 39851, 441912, 4896043, 54248371, 601050906, 6659404865, 73783381595, 817488259440, 9057417947527, 100352286120727, 1111860046543146, 12318929680916909, 136488426454208783, 1512232882805726640 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 2 of A221192.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..20

FORMULA

Empirical: a(n) = 15*a(n-1) - 41*a(n-2) - 42*a(n-3) + 174*a(n-4) - 86*a(n-5) - 2*a(n-6).

Empirical g.f.: x*(1 + 16*x - 106*x^2 + 148*x^3 - 58*x^4) / (1 - 15*x + 41*x^2 + 42*x^3 - 174*x^4 + 86*x^5 + 2*x^6). - Colin Barker, Mar 14 2018

EXAMPLE

Some solutions for n=3:

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

..1..3....0..1....0..1....0..1....1..1....1..2....2..0....2..1....4..0....2..0

..1..1....2..1....3..0....0..1....2..2....1..1....1..3....1..0....0..1....0..2

CROSSREFS

Cf. A221192.

Sequence in context: A142382 A137318 A182025 * A029813 A138697 A186071

Adjacent sequences:  A221186 A221187 A221188 * A221190 A221191 A221192

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 04 2013

STATUS

approved

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Last modified April 15 10:49 EDT 2021. Contains 342977 sequences. (Running on oeis4.)