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A283629 Number of nX3 0..1 arrays with no 1 equal to more than one of its horizontal, diagonal and antidiagonal neighbors, with the exception of exactly two elements. 1
0, 0, 37, 388, 3729, 28828, 203025, 1325980, 8216341, 48912768, 282293033, 1589466368, 8771503165, 47606031352, 254776347029, 1347286728096, 7051427209337, 36575153581764, 188217385278837, 961810924181084 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Column 3 of A283634.

LINKS

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

FORMULA

Empirical: a(n) = 15*a(n-1) -78*a(n-2) +134*a(n-3) +162*a(n-4) -840*a(n-5) +728*a(n-6) +1398*a(n-7) -3117*a(n-8) +413*a(n-9) +4626*a(n-10) -4056*a(n-11) -2576*a(n-12) +5376*a(n-13) -768*a(n-14) -3200*a(n-15) +1536*a(n-16) +768*a(n-17) -512*a(n-18)

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Cf. A283634.

Sequence in context: A178613 A124337 A027944 * A264626 A201789 A115926

Adjacent sequences:  A283626 A283627 A283628 * A283630 A283631 A283632

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 12 2017

STATUS

approved

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Last modified January 28 22:40 EST 2020. Contains 331328 sequences. (Running on oeis4.)