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A196642 Number of nXn 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 1,3,4,0,2 for x=0,1,2,3,4 0
1, 1, 16, 129, 4273, 217880, 23946130, 5094296927, 2171426372387, 1837082082523359, 3094534584891471987, 10360619358796873163844, 68989834793646571143250669, 913590557002024874434691467840 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Every 0 is next to 0 1's, every 1 is next to 1 3's, every 2 is next to 2 4's, every 3 is next to 3 0's, every 4 is next to 4 2's

Diagonal of A196646

LINKS

Table of n, a(n) for n=1..14.

EXAMPLE

Some solutions for n=4

..0..0..0..0....0..0..3..0....0..0..0..0....0..0..0..0....0..0..3..0

..0..3..0..3....0..0..0..0....3..0..3..0....0..0..0..0....3..0..0..0

..0..3..0..0....3..0..0..3....0..0..3..0....0..3..3..0....0..3..3..0

..0..0..3..0....0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0

CROSSREFS

Sequence in context: A031156 A099195 A041486 * A196595 A055914 A183535

Adjacent sequences:  A196639 A196640 A196641 * A196643 A196644 A196645

KEYWORD

nonn

AUTHOR

R. H. Hardin Oct 04 2011

STATUS

approved

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Last modified November 21 12:45 EST 2014. Contains 249778 sequences.