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A210814 Number of (n+1)X(n+1) 0..3 symmetric matrices containing all values 0..3 with every 2X2 subblock having two distinct values, and new values 0..3 introduced in lower triangle row major order 0
0, 1, 100, 6684, 599536, 82309141, 18679289180, 7191882371599, 4794826023217991, 5595844097524199026, 11523237615776387849625, 42103142637653897079485507 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..12.

EXAMPLE

Some solutions for n=3

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

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

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

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

CROSSREFS

Sequence in context: A053109 A151647 A245666 * A065689 A260859 A117687

Adjacent sequences:  A210811 A210812 A210813 * A210815 A210816 A210817

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 27 2012

STATUS

approved

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Last modified December 8 17:01 EST 2021. Contains 349596 sequences. (Running on oeis4.)