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A268885 Number of nX7 binary arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once. 1
38, 1340, 42362, 1187838, 31427480, 800733668, 19876401224, 483987898760, 11611969197776, 275345016177616, 6466964539799840, 150689548401385312, 3487912674084234304, 80273121207141357120, 1838370376874099584640 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A268886.

LINKS

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

FORMULA

Empirical: a(n) = 68*a(n-1) -1804*a(n-2) +24560*a(n-3) -195400*a(n-4) +974752*a(n-5) -3171360*a(n-6) +6871936*a(n-7) -9999248*a(n-8) +9740096*a(n-9) -6250176*a(n-10) +2552576*a(n-11) -621824*a(n-12) +79872*a(n-13) -4096*a(n-14) for n>16

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Cf. A268886.

Sequence in context: A239043 A137030 A027657 * A162858 A163221 A163660

Adjacent sequences:  A268882 A268883 A268884 * A268886 A268887 A268888

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 15 2016

STATUS

approved

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Last modified December 4 12:10 EST 2021. Contains 349490 sequences. (Running on oeis4.)