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A317898 Number of nX4 0..1 arrays with every element unequal to 2, 3 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. 1
0, 2, 3, 13, 31, 54, 116, 342, 956, 2459, 6366, 16404, 42964, 112558, 294354, 768840, 2007738, 5246415, 13708041, 35818742, 93591255, 244546559, 638982739, 1669591197, 4362471879, 11398715036, 29783832169, 77822515690, 203343065801 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 4 of A317902.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +2*a(n-2) +3*a(n-3) +4*a(n-4) +12*a(n-5) +3*a(n-6) -3*a(n-7) -39*a(n-8) -52*a(n-9) -83*a(n-10) -74*a(n-11) -30*a(n-12) +123*a(n-13) +206*a(n-14) +254*a(n-15) +83*a(n-16) +26*a(n-17) -41*a(n-18) -47*a(n-19) -79*a(n-20) -34*a(n-21) -41*a(n-22) +11*a(n-23) -18*a(n-24) -3*a(n-25) +7*a(n-26) +5*a(n-27) -6*a(n-28) +4*a(n-29) -a(n-30) for n>34

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A317902.

Sequence in context: A233523 A256712 A092175 * A317187 A296291 A072997

Adjacent sequences:  A317895 A317896 A317897 * A317899 A317900 A317901

KEYWORD

nonn

AUTHOR

R. H. Hardin, Aug 10 2018

STATUS

approved

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Last modified May 21 06:36 EDT 2022. Contains 353889 sequences. (Running on oeis4.)