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A211102 1/4 the number of (n+1)X(n+1) 0..3 symmetric matrices with every 2X2 subblock having one or two distinct values 1
10, 184, 6304, 416368, 54050896, 13894956304, 7116012826192, 7287811488547552, 14966388560597031328, 61754027537691698147200, 512742718215616709255295136, 8576912248102024129584312864160 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..13

EXAMPLE

Some solutions for n=3

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

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

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

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

CROSSREFS

Sequence in context: A304936 A239764 A179521 * A121973 A223146 A239765

Adjacent sequences:  A211099 A211100 A211101 * A211103 A211104 A211105

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 31 2012

STATUS

approved

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Last modified December 13 17:17 EST 2019. Contains 329970 sequences. (Running on oeis4.)