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A305681 Number of nX4 0..1 arrays with every element unequal to 0, 2, 3, 4, 5 or 6 king-move adjacent elements, with upper left element zero. 2
1, 24, 139, 1595, 17947, 207116, 2403703, 27979008, 325990496, 3799972909, 44303294071, 516563566397, 6023170715786, 70231536050457, 818919946988978, 9548863433870338, 111342842876041149, 1298294120431505145 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 4 of A305685.

LINKS

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

FORMULA

Empirical: a(n) = 13*a(n-1) -8*a(n-2) -31*a(n-3) -662*a(n-4) -349*a(n-5) +1502*a(n-6) +8784*a(n-7) +13283*a(n-8) -11362*a(n-9) -58698*a(n-10) -93170*a(n-11) +22530*a(n-12) +212222*a(n-13) +239055*a(n-14) -97186*a(n-15) -516629*a(n-16) -362074*a(n-17) +344826*a(n-18) +796028*a(n-19) +348333*a(n-20) -439739*a(n-21) -544731*a(n-22) -38218*a(n-23) +322198*a(n-24) +234374*a(n-25) -15275*a(n-26) -89120*a(n-27) -53909*a(n-28) -61978*a(n-29) -66424*a(n-30) -7834*a(n-31) +8874*a(n-32) +1234*a(n-33) +1640*a(n-34) -636*a(n-35) +240*a(n-36) +208*a(n-37) -192*a(n-38) for n>40

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A305685.

Sequence in context: A223409 A205343 A267631 * A199827 A223471 A219988

Adjacent sequences:  A305678 A305679 A305680 * A305682 A305683 A305684

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jun 08 2018

STATUS

approved

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Last modified November 28 21:30 EST 2021. Contains 349415 sequences. (Running on oeis4.)