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A269010 Number of nX7 binary arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two exactly once. 1
38, 696, 18210, 390064, 8134304, 164351184, 3258530608, 63679868768, 1230707111424, 23573013881888, 448188039743360, 8468276406290880, 159151109503787520, 2977237536021550208, 55469798154343791232 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A269011.

LINKS

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

FORMULA

Empirical: a(n) = 60*a(n-1) -1352*a(n-2) +13344*a(n-3) -35948*a(n-4) -311480*a(n-5) +1985472*a(n-6) +1821840*a(n-7) -31021776*a(n-8) +4125984*a(n-9) +251967152*a(n-10) -46853056*a(n-11) -1173410880*a(n-12) -138650624*a(n-13) +2912101888*a(n-14) +1295316992*a(n-15) -3360870400*a(n-16) -2339016704*a(n-17) +1368141824*a(n-18) +1168457728*a(n-19) -291553280*a(n-20) -245170176*a(n-21) +45023232*a(n-22) +19922944*a(n-23) -4194304*a(n-24) for n>25

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Cf. A269011.

Sequence in context: A089271 A195912 A240425 * A010954 A035714 A161651

Adjacent sequences:  A269007 A269008 A269009 * A269011 A269012 A269013

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 17 2016

STATUS

approved

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Last modified August 7 06:24 EDT 2020. Contains 336274 sequences. (Running on oeis4.)