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A281404 Number of 5Xn 0..1 arrays with no element equal to more than two of its horizontal, diagonal or antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards. 1
0, 160, 1413, 2886, 5892, 10130, 16241, 25680, 41353, 67226, 108849, 176500, 287083, 467706, 762549, 1242828, 2024499, 3295966, 5361623, 8713840, 14148393, 22950214, 37193019, 60220156, 97418383, 157461854, 254309175, 410409716, 661848005 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row 5 of A281400.

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) -6*a(n-2) +6*a(n-3) -7*a(n-4) +8*a(n-5) -9*a(n-6) +8*a(n-7) -5*a(n-8) +4*a(n-9) -3*a(n-10) +2*a(n-11) -a(n-12) for n>19

EXAMPLE

Some solutions for n=4

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

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

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

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

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

CROSSREFS

Cf. A281400.

Sequence in context: A236518 A120103 A235655 * A127409 A013447 A013446

Adjacent sequences:  A281401 A281402 A281403 * A281405 A281406 A281407

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 21 2017

STATUS

approved

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Last modified February 25 11:46 EST 2021. Contains 341606 sequences. (Running on oeis4.)