A267725 - OEIS

A267725

Number of 2Xn arrays containing n copies of 0..2-1 with every element equal to at least one horizontal neighbor and the top left element equal to 0.

0, 1, 1, 3, 5, 12, 26, 60, 143, 353, 879, 2200, 5528, 13963, 35421, 90122, 229729, 586438, 1498966, 3836099, 9827905, 25202549, 64683193, 166137751, 427022480, 1098291533, 2826500851, 7278246356, 18751418071, 48334451894, 124647030884

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OFFSET

1,4

COMMENTS

Row 2 of A267724.

LINKS

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

EXAMPLE

Some solutions for n=6

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

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

CROSSREFS

Cf. A267724.

Sequence in context: A017921 A280000 A241097 * A161762 A245649 A291035

Adjacent sequences: A267722 A267723 A267724 * A267726 A267727 A267728

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 20 2016

STATUS

approved