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Revision History for A186166

(Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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1/4 the number of n X 7 0..3 arrays with every element equal to exactly one or two of its horizontal and vertical neighbors.
(history; published version)

#6 by Wesley Ivan Hurt at Mon Apr 26 21:13:31 EDT 2021

STATUS

editing

approved

#5 by Wesley Ivan Hurt at Mon Apr 26 21:13:20 EDT 2021

NAME

1/4 the number of nX7 n X 7 0..3 arrays with every element equal to exactly one or two of its horizontal and vertical neighbors.

COMMENTS

Column 7 of A186168.

EXAMPLE

Some solutions for 4X7 4 X 7 with a(1,1) = 0

CROSSREFS

Cf. A186168.

STATUS

approved

editing

#4 by Russ Cox at Sat Mar 31 12:36:04 EDT 2012

AUTHOR

_R. H. Hardin (rhhardin(AT)att.net) _ Feb 13 2011

Discussion

Sat Mar 31

12:36

OEIS Server: https://oeis.org/edit/global/875

#3 by Ron Hardin at Sun Feb 13 21:09:44 EST 2011

STATUS

proposed

approved

#2 by Ron Hardin at Sun Feb 13 21:09:35 EST 2011

NAME

allocated for Ron Hardin1/4 the number of nX7 0..3 arrays with every element equal to exactly one or two of its horizontal and vertical neighbors

DATA

40, 99933, 87054174, 95752776009, 96951738076992, 101554003879403823

OFFSET

1,1

COMMENTS

Column 7 of A186168

EXAMPLE

Some solutions for 4X7 with a(1,1)=0

..0..0..2..0..0..0..1....0..0..2..0..0..3..0....0..0..2..0..0..0..0

..0..0..2..0..2..2..1....0..0..2..0..3..3..0....0..0..2..0..2..2..1

..2..2..0..2..3..3..1....2..2..0..2..3..0..1....2..2..0..1..2..1..1

..0..0..0..2..3..2..2....0..0..0..2..0..0..1....0..0..0..1..1..3..3

KEYWORD

allocated

nonn

AUTHOR

R. H. Hardin (rhhardin(AT)att.net) Feb 13 2011

STATUS

approved

proposed

#1 by Ron Hardin at Sun Feb 13 21:03:34 EST 2011

NAME

allocated for Ron Hardin

KEYWORD

allocated

STATUS

approved