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A305085 Number of nX4 0..1 arrays with every element unequal to 1, 2, 3, 6 or 7 king-move adjacent elements, with upper left element zero. 1
2, 33, 34, 91, 352, 372, 1016, 3474, 4945, 13288, 37062, 64155, 165994, 415987, 812826, 2026972, 4818456, 10116447, 24515337, 56876113, 124413665, 295467341, 678580178, 1518490899, 3558083669, 8143158484, 18447074191, 42855072254 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A305089.

LINKS

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

FORMULA

Empirical: a(n) = 3*a(n-1) +6*a(n-3) -31*a(n-4) +6*a(n-5) +10*a(n-6) +73*a(n-7) -15*a(n-8) -70*a(n-9) -42*a(n-10) -6*a(n-11) +63*a(n-12) +32*a(n-13) +12*a(n-14) -25*a(n-15) -20*a(n-16) -3*a(n-17) +4*a(n-18) +4*a(n-19) for n>24

EXAMPLE

Some solutions for n=5

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

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

..1..1..1..1. .1..1..1..1. .1..1..1..1. .1..1..1..1. .1..1..1..1

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

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

CROSSREFS

Cf. A305089.

Sequence in context: A304145 A305485 A078732 * A042251 A316736 A199551

Adjacent sequences:  A305082 A305083 A305084 * A305086 A305087 A305088

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 25 2018

STATUS

approved

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Last modified August 14 09:14 EDT 2020. Contains 336480 sequences. (Running on oeis4.)