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A304844 Number of nX4 0..1 arrays with every element unequal to 0, 1, 2, 4 or 7 king-move adjacent elements, with upper left element zero. 1
8, 24, 51, 132, 502, 1638, 4816, 15697, 51711, 162366, 515716, 1666971, 5329280, 16966976, 54361108, 174123735, 556206198, 1778536970, 5692126701, 18203527304, 58206977546, 186193045751, 595556243811, 1904654103039, 6091785970264 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A304848.

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) +4*a(n-2) +10*a(n-3) -12*a(n-4) -70*a(n-5) -57*a(n-6) +109*a(n-7) +258*a(n-8) +80*a(n-9) -206*a(n-10) -210*a(n-11) -54*a(n-12) -493*a(n-13) -200*a(n-14) +1067*a(n-15) +336*a(n-16) -258*a(n-17) +16*a(n-18) +129*a(n-19) +71*a(n-20) -951*a(n-21) -578*a(n-22) +1082*a(n-23) -246*a(n-24) +3*a(n-25) +1259*a(n-26) -962*a(n-27) -842*a(n-28) +848*a(n-29) -98*a(n-30) -294*a(n-31) +282*a(n-32) +48*a(n-33) -72*a(n-34) for n>38

EXAMPLE

Some solutions for n=5

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

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

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

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

CROSSREFS

Cf. A304848.

Sequence in context: A028612 A068857 A064225 * A054275 A256857 A122655

Adjacent sequences:  A304841 A304842 A304843 * A304845 A304846 A304847

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 19 2018

STATUS

approved

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Last modified July 18 15:42 EDT 2019. Contains 325144 sequences. (Running on oeis4.)