A221335 Number of nX3 arrays of occupancy after each element stays put or moves to some king-move neighbor, with every occupancy equal to zero or two

0, 20, 0, 790, 0, 34042, 0, 1470618, 0, 63526554, 0, 2744129114, 0, 118536728562, 0, 5120367434418, 0, 221181729631882, 0, 9554266491058090, 0, 412710429318366178, 0, 17827626812331482594, 0, 770090248640353835354, 0

Offset

1,2

Comments

Column 3 of A221337

Links

R. H. Hardin, Table of n, a(n) for n = 1..30

Formula

Empirical: a(n) = 66*a(n-2) -1131*a(n-4) +6726*a(n-6) -18808*a(n-8) +27860*a(n-10) -19388*a(n-12) +3240*a(n-14)

Crossrefs

Sequence in context: A008426 A055637 A086684 * A298672 A198800 A060430

Adjacent sequences: A221332 A221333 A221334 * A221336 A221337 A221338

Keyword

nonn

Author

R. H. Hardin Jan 11 2013

Status

approved