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A318547 Number of nX3 0..1 arrays with every element unequal to 1, 2, 4 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. 1
1, 6, 5, 21, 44, 106, 258, 600, 1476, 3461, 8382, 19993, 47986, 115062, 275759, 661860, 1587148, 3808959, 9139148, 21934213, 52643142, 126358591, 303319238, 728132846, 1748027976, 4196626333, 10075548717, 24190744152, 58081944604, 139457643789 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 3 of A318552.

LINKS

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

FORMULA

Empirical: a(n) = 6*a(n-2) +10*a(n-3) -4*a(n-4) -39*a(n-5) -51*a(n-6) +7*a(n-7) +78*a(n-8) +78*a(n-9) +a(n-10) -54*a(n-11) -4*a(n-12) +34*a(n-13) +4*a(n-14) -15*a(n-15) -6*a(n-16) +33*a(n-17) +29*a(n-18) -38*a(n-19) -40*a(n-20) +11*a(n-21) +5*a(n-22) +2*a(n-23) -8*a(n-24) -5*a(n-25) +14*a(n-26) -4*a(n-27) -6*a(n-28) +5*a(n-29) +a(n-30) -a(n-31)

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A318552.

Sequence in context: A281175 A281221 A143130 * A082384 A248265 A267284

Adjacent sequences:  A318544 A318545 A318546 * A318548 A318549 A318550

KEYWORD

nonn

AUTHOR

R. H. Hardin, Aug 28 2018

STATUS

approved

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Last modified May 21 09:30 EDT 2022. Contains 353908 sequences. (Running on oeis4.)