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A305343 Number of nX4 0..1 arrays with every element unequal to 0, 1, 3, 5 or 8 king-move adjacent elements, with upper left element zero. 2
5, 21, 28, 77, 199, 454, 1074, 2619, 6216, 14782, 35494, 84850, 202493, 484472, 1158594, 2768565, 6619260, 15826963, 37833884, 90447825, 216242881, 516964232, 1235890365, 2954669861, 7063719452, 16887142919, 40372113631, 96517561505 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A305347.

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) +4*a(n-3) -3*a(n-4) -4*a(n-5) +7*a(n-6) -8*a(n-7) +a(n-8) -21*a(n-9) +5*a(n-10) +10*a(n-11) -7*a(n-12) +8*a(n-13) -3*a(n-14) +34*a(n-15) +7*a(n-16) +2*a(n-17) -a(n-18) +5*a(n-20) -16*a(n-21) -12*a(n-22) -17*a(n-23) -3*a(n-25) -4*a(n-26) -4*a(n-27) +a(n-28) +10*a(n-29) +3*a(n-30) +a(n-31) +a(n-32) +3*a(n-33) +2*a(n-34) -a(n-35) -a(n-36) for n>37

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A305347.

Sequence in context: A304351 A305914 A303036 * A186304 A316235 A317156

Adjacent sequences:  A305340 A305341 A305342 * A305344 A305345 A305346

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 30 2018

STATUS

approved

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Last modified December 7 16:59 EST 2021. Contains 349581 sequences. (Running on oeis4.)