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A297722 Number of 3Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1, 2 or 4 neighboring 1s. 1
1, 29, 145, 523, 2717, 14462, 68919, 332306, 1652441, 8140067, 39816114, 195543171, 961617387, 4722204339, 23186542778, 113898106759, 559470061363, 2747805117373, 13496167444555, 66289849507630, 325594360281088 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row 3 of A297720.

LINKS

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

FORMULA

Empirical: a(n) = 6*a(n-1) -5*a(n-2) +6*a(n-3) -17*a(n-4) -168*a(n-5) +284*a(n-6) +316*a(n-7) -636*a(n-8) +40*a(n-9) +732*a(n-10) -863*a(n-11) -414*a(n-12) +846*a(n-13) +17*a(n-14) -297*a(n-15) +188*a(n-16) +50*a(n-17) -52*a(n-18)

EXAMPLE

Some solutions for n=7

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

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

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

CROSSREFS

Cf. A297720.

Sequence in context: A299109 A302542 A123845 * A042642 A172075 A042644

Adjacent sequences:  A297719 A297720 A297721 * A297723 A297724 A297725

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 04 2018

STATUS

approved

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Last modified November 30 05:12 EST 2021. Contains 349419 sequences. (Running on oeis4.)