A282185 - OEIS

A282185

Number of n X 2 0..2 arrays with no element equal to more than four of its king-move neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

0, 0, 1, 8, 104, 1222, 13552, 144784, 1506870, 15382464, 154705344, 1537619888, 15136209536, 147816712064, 1433881609384, 13829678601088, 132726827340160, 1268315293540128, 12073757901185280, 114548957745270528

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OFFSET

1,4

LINKS

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

FORMULA

Empirical: a(n) = 16*a(n-1) - 48*a(n-2) - 116*a(n-3) - 160*a(n-4) - 96*a(n-5) - 36*a(n-6) for n>9.

Empirical g.f.: x^3*(1 - 8*x + 24*x^2 + 58*x^3 + 80*x^4 + 48*x^5 + 18*x^6) / (1 - 8*x - 8*x^2 - 6*x^3)^2. - Colin Barker, Feb 20 2019

EXAMPLE

All solutions for n=4:

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

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

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

CROSSREFS

Column 2 of A282189.

Sequence in context: A335608 A109774 A001657 * A354064 A106260 A112121

Adjacent sequences: A282182 A282183 A282184 * A282186 A282187 A282188

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 08 2017

STATUS

approved