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A303085 Number of 3Xn 0..1 arrays with every element equal to 0, 2, 3, 4 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. 1
4, 2, 32, 29, 258, 432, 2525, 6313, 30188, 97855, 428478, 1605301, 6821375, 27390903, 115569231, 478335810, 2017576268, 8457463080, 35707225807, 150472100292, 635822248364, 2685274511197, 11352580693193, 47989709554314 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 3 of A303084.

LINKS

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

FORMULA

Empirical: a(n) = 7*a(n-1) -2*a(n-2) -67*a(n-3) +80*a(n-4) +187*a(n-5) -202*a(n-6) -298*a(n-7) +122*a(n-8) +213*a(n-9) +122*a(n-10) +126*a(n-11) -63*a(n-12) -416*a(n-13) +152*a(n-14) +20*a(n-15) -21*a(n-16) +9*a(n-17) for n>18

EXAMPLE

Some solutions for n=5

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

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

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

CROSSREFS

Cf. A303084.

Sequence in context: A076936 A344536 A348567 * A086482 A078758 A102015

Adjacent sequences:  A303082 A303083 A303084 * A303086 A303087 A303088

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 18 2018

STATUS

approved

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Last modified December 6 18:16 EST 2021. Contains 349567 sequences. (Running on oeis4.)