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A305178 Number of nX4 0..1 arrays with every element unequal to 1, 2, 5, 6 or 7 king-move adjacent elements, with upper left element zero. 1
2, 1, 9, 10, 13, 47, 71, 118, 241, 453, 870, 1608, 3110, 6075, 11491, 22105, 42831, 82321, 158514, 305836, 589983, 1137829, 2194384, 4234349, 8170446, 15762684, 30415495, 58692610, 113253536, 218539740, 421716458, 813790085, 1570376360 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A305182.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +a(n-2) +3*a(n-3) -2*a(n-5) -5*a(n-6) -3*a(n-7) -2*a(n-9) +a(n-10) +2*a(n-11) for n>18

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A305182.

Sequence in context: A132744 A059604 A048160 * A295851 A192324 A063579

Adjacent sequences:  A305175 A305176 A305177 * A305179 A305180 A305181

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 26 2018

STATUS

approved

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Last modified July 15 23:32 EDT 2020. Contains 335774 sequences. (Running on oeis4.)