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A297608 Number of 2Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 0, 1 or 3 neighboring 1s. 1
4, 11, 35, 96, 281, 829, 2428, 7059, 20611, 60296, 176129, 514221, 1501988, 4388011, 12817075, 37436160, 109349737, 319411997, 932986892, 2725199619, 7960200227, 23251456696, 67916501713, 198381124173, 579463016116, 1692587480411 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 2 of A297607.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +3*a(n-2) +4*a(n-3) +12*a(n-4) -12*a(n-6)

EXAMPLE

Some solutions for n=7

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

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

CROSSREFS

Cf. A297607.

Sequence in context: A149236 A135919 A034755 * A034756 A029853 A104500

Adjacent sequences:  A297605 A297606 A297607 * A297609 A297610 A297611

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 01 2018

STATUS

approved

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Last modified June 21 00:55 EDT 2021. Contains 345329 sequences. (Running on oeis4.)