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A305241 Number of nX4 0..1 arrays with every element unequal to 0, 1, 2, 4 or 8 king-move adjacent elements, with upper left element zero. 1
8, 24, 32, 94, 273, 767, 2128, 6150, 17387, 49477, 140832, 401136, 1140970, 3248777, 9248091, 26325969, 74939305, 213335733, 607295337, 1728785729, 4921333566, 14009574825, 39881001737, 113529283100, 323183797078, 920007268842 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A305245.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +5*a(n-2) +4*a(n-3) +a(n-4) -20*a(n-5) -26*a(n-6) -9*a(n-7) -a(n-8) +39*a(n-9) +53*a(n-10) +39*a(n-11) +15*a(n-12) -6*a(n-13) -31*a(n-14) -54*a(n-15) -53*a(n-16) -26*a(n-17) +28*a(n-18) +18*a(n-19) +10*a(n-20) -a(n-21) -54*a(n-22) -24*a(n-23) +13*a(n-24) -5*a(n-25) -4*a(n-26) +5*a(n-27) +2*a(n-28) for n>32

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A305245.

Sequence in context: A319528 A140403 A108578 * A044450 A134223 A304475

Adjacent sequences:  A305238 A305239 A305240 * A305242 A305243 A305244

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 28 2018

STATUS

approved

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Last modified October 26 20:42 EDT 2021. Contains 348269 sequences. (Running on oeis4.)