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A220430 T(n,k)=Equals two maps: number of nXk binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal and vertical neighbors in a random 0..3 nXk array 3
1, 1, 1, 2, 6, 2, 4, 23, 23, 4, 7, 94, 236, 94, 7, 12, 380, 2103, 2103, 380, 12, 21, 1494, 18366, 40412, 18366, 1494, 21, 37, 5939, 155250, 735555, 735555, 155250, 5939, 37, 65, 23398, 1286012, 12702453, 26927902, 12702453, 1286012, 23398, 65, 114, 92317 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Table starts

..1.....1.......2........4........7.......12........21.......37....65.114

..1.....6......23.......94......380.....1494......5939....23398.92317

..2....23.....236.....2103....18366...155250...1286012.10530541

..4....94....2103....40412...735555.12702453.213282872

..7...380...18366...735555.26927902

.12..1494..155250.12702453

.21..5939.1286012

.37.23398

.65

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..49

EXAMPLE

Some solutions for n=3 k=4

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

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

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

CROSSREFS

Column 1 is A005251(n+1)

Column 2 is A220372

Sequence in context: A085193 A220242 A220375 * A220279 A221188 A220532

Adjacent sequences:  A220427 A220428 A220429 * A220431 A220432 A220433

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin Dec 14 2012

STATUS

approved

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Last modified February 26 00:08 EST 2020. Contains 332270 sequences. (Running on oeis4.)