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A296646 Number of n X 3 0..1 arrays with each 1 adjacent to 0, 1 or 3 king-move neighboring 1s. 1
7, 29, 111, 468, 1985, 8126, 33933, 141664, 588156, 2449547, 10201129, 42445694, 176698722, 735575546, 3061694857, 12744724374, 53051527226, 220828964794, 919220181758, 3826333903711, 15927393968521, 66299068852883 (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) = 2*a(n-1) + 6*a(n-2) + 18*a(n-3) - 12*a(n-4) - 42*a(n-5) - 17*a(n- 6) + 9*a(n-7) + 7*a(n-8) + 13*a(n-9) + 2*a(n-10).

Empirical g.f.: x*(7 + 15*x + 11*x^2 - 54*x^3 - 55*x^4 - 8*x^5 + 16*x^6 + 20*x^7 + 15*x^8 + 2*x^9) / (1 - 2*x - 6*x^2 - 18*x^3 + 12*x^4 + 42*x^5 + 17*x^6 - 9*x^7 - 7*x^8 - 13*x^9 - 2*x^10). - Colin Barker, Feb 24 2019

EXAMPLE

Some solutions for n=7:

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

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

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

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

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

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

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

CROSSREFS

Column 3 of A296651.

Sequence in context: A246038 A049349 A124828 * A037094 A118171 A072261

Adjacent sequences:  A296643 A296644 A296645 * A296647 A296648 A296649

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 17 2017

STATUS

approved

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Last modified November 19 00:12 EST 2019. Contains 329310 sequences. (Running on oeis4.)