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A283381 Number of nX3 0..1 arrays with no 1 equal to more than two of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements. 1
0, 3, 60, 532, 4420, 34531, 257416, 1862717, 13180270, 91663499, 628776285, 4264929188, 28658352573, 191042638980, 1264824631815, 8324053254833, 54494796078919, 355096961618473, 2304221229952838, 14895901458999710 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 3 of A283386.

LINKS

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

FORMULA

Empirical: a(n) = 15*a(n-1) -59*a(n-2) -23*a(n-3) +174*a(n-4) +801*a(n-5) +482*a(n-6) -304*a(n-7) -1907*a(n-8) -201*a(n-9) +416*a(n-10) +2195*a(n-11) -1927*a(n-12) +144*a(n-13) -2255*a(n-14) +4199*a(n-15) -2655*a(n-16) +3200*a(n-17) -5076*a(n-18) +5003*a(n-19) -4510*a(n-20) +5401*a(n-21) -5925*a(n-22) +5360*a(n-23) -4834*a(n-24) +4242*a(n-25) -3201*a(n-26) +2056*a(n-27) -1214*a(n-28) +632*a(n-29) -252*a(n-30) +64*a(n-31) -8*a(n-32)

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Cf. A283386.

Sequence in context: A183286 A195560 A229749 * A002738 A006432 A195550

Adjacent sequences:  A283378 A283379 A283380 * A283382 A283383 A283384

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 06 2017

STATUS

approved

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Last modified November 27 03:56 EST 2021. Contains 349345 sequences. (Running on oeis4.)