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A252515 Number of (n+2)X(n+2) 0..3 arrays with every 3X3 subblock row and column sum not equal to 0 2 4 6 or 7 and every 3X3 diagonal and antidiagonal sum equal to 0 2 4 6 or 7 0
806, 432, 1783, 5628, 74181, 1215491, 6486931, 304232630, 16970081459, 108911061618, 18397477779099, 3657274585418076, 25856975096624206, 16084237513106982571, 11697931298387098661798, 86957945614794531238579 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Diagonal of A252523

LINKS

Table of n, a(n) for n=1..16.

EXAMPLE

Some solutions for n=4

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

..1..2..2..1..2..2....2..2..1..2..2..1....2..1..2..2..1..2....2..1..2..2..1..2

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

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

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

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

CROSSREFS

Sequence in context: A267932 A267979 A249877 * A252516 A252523 A243858

Adjacent sequences:  A252512 A252513 A252514 * A252516 A252517 A252518

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 18 2014

STATUS

approved

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Last modified January 29 01:49 EST 2020. Contains 331328 sequences. (Running on oeis4.)