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A297734 Number of 2Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 2 or 4 neighboring 1s. 1
1, 2, 8, 15, 32, 61, 145, 297, 658, 1352, 2975, 6240, 13565, 28609, 61801, 131106, 282136, 600239, 1288448, 2746557, 5887025, 12563881, 26904370, 57460200, 122975935, 262760096, 562158461, 1201484193, 2569940969, 5493595714 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row 2 of A297733.

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) +a(n-2) -3*a(n-3) +6*a(n-4) -6*a(n-5)

EXAMPLE

Some solutions for n=7

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

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

CROSSREFS

Cf. A297733.

Sequence in context: A189952 A077598 A095298 * A100596 A295937 A305674

Adjacent sequences:  A297731 A297732 A297733 * A297735 A297736 A297737

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 04 2018

STATUS

approved

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Last modified September 18 02:31 EDT 2021. Contains 347504 sequences. (Running on oeis4.)