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A297596 Number of 3 X n 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1 or 5 neighboring 1s. 1
1, 9, 25, 49, 145, 443, 1141, 3009, 8455, 23151, 62211, 169651, 464469, 1262947, 3434407, 9364725, 25517397, 69467533, 189209921, 515479315, 1403998341, 3823905513, 10415880295, 28371283095, 77275911315, 210482481315 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) + a(n-2) + 8*a(n-3) + 7*a(n-4) - 8*a(n-6) - 6*a(n-7).

Empirical g.f.: x*(1 + 8*x + 15*x^2 + 7*x^3 - 8*x^4 - 14*x^5 - 6*x^6) / (1 - x - x^2 - 8*x^3 - 7*x^4 + 8*x^6 + 6*x^7). - Colin Barker, Mar 01 2019

EXAMPLE

Some solutions for n=7:

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

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

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

CROSSREFS

Row 3 of A297595.

Sequence in context: A282631 A245694 A045972 * A266132 A112629 A225322

Adjacent sequences:  A297593 A297594 A297595 * A297597 A297598 A297599

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 01 2018

STATUS

approved

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Last modified October 31 05:06 EDT 2020. Contains 338098 sequences. (Running on oeis4.)