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A306168 Number of nX4 0..1 arrays with every element unequal to 0, 1, 3, 5, 6 or 7 king-move adjacent elements, with upper left element zero. 1
5, 21, 30, 93, 249, 544, 1372, 3411, 8269, 20472, 50397, 123803, 305272, 751590, 1849735, 4556239, 11219928, 27625541, 68032151, 167535478, 412552316, 1015939459, 2501834023, 6160893450, 15171602577, 37361209577, 92004521524 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A306172.

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) +16*a(n-3) -26*a(n-4) -3*a(n-5) -103*a(n-6) +137*a(n-7) +32*a(n-8) +371*a(n-9) -406*a(n-10) -152*a(n-11) -915*a(n-12) +801*a(n-13) +422*a(n-14) +1710*a(n-15) -1092*a(n-16) -751*a(n-17) -2415*a(n-18) +1006*a(n-19) +977*a(n-20) +2609*a(n-21) -505*a(n-22) -986*a(n-23) -2180*a(n-24) -154*a(n-25) +630*a(n-26) +1281*a(n-27) +325*a(n-28) -267*a(n-29) -512*a(n-30) -276*a(n-31) -13*a(n-32) +49*a(n-33) +74*a(n-34) +52*a(n-35) +32*a(n-36) +11*a(n-37) -7*a(n-38) -6*a(n-39) -3*a(n-40) for n>41

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A306172.

Sequence in context: A316235 A317156 A304665 * A305645 A316921 A316423

Adjacent sequences:  A306165 A306166 A306167 * A306169 A306170 A306171

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jun 23 2018

STATUS

approved

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Last modified December 5 23:38 EST 2021. Contains 349558 sequences. (Running on oeis4.)