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A304220 Number of nX7 0..1 arrays with every element unequal to 0, 1, 3 or 8 king-move adjacent elements, with upper left element zero. 1
21, 103, 93, 190, 509, 1628, 4263, 11307, 32315, 89108, 241808, 671482, 1860876, 5112838, 14112560, 39021398, 107604674, 296850358, 819720184, 2262238142, 6242240358, 17229841514, 47554661392, 131237610194, 362206032762 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A304221.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +a(n-2) +10*a(n-3) +5*a(n-4) -2*a(n-5) -13*a(n-6) -16*a(n-7) -8*a(n-8) +10*a(n-9) +22*a(n-10) +9*a(n-11) -20*a(n-12) -22*a(n-13) -4*a(n-14) +14*a(n-15) +12*a(n-16) +6*a(n-17) -6*a(n-18) for n>24

EXAMPLE

Some solutions for n=7

..0..0..0..0..0..0..0. .0..0..0..0..0..0..0. .0..0..0..0..0..0..0

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

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

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

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

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

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

CROSSREFS

Cf. A304221.

Sequence in context: A208538 A303681 A304132 * A305481 A219385 A219297

Adjacent sequences:  A304217 A304218 A304219 * A304221 A304222 A304223

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 08 2018

STATUS

approved

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Last modified June 14 09:06 EDT 2021. Contains 345018 sequences. (Running on oeis4.)