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A252300
Number of (n+2)X(3+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 1 3 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 1 3 6 or 7
1
1675, 1370, 1677, 2151, 3669, 5416, 7492, 13386, 20379, 28688, 51938, 79730, 112972, 205370, 316178, 449108, 817514, 1260050, 1791652, 3262922, 5031698, 7157828, 13038218, 20110610, 28614532, 52126730, 80410898, 114425348, 208455434
OFFSET
1,1
COMMENTS
Column 3 of A252305
LINKS
FORMULA
Empirical: a(n) = 7*a(n-3) -14*a(n-6) +8*a(n-9) for n>18
EXAMPLE
Some solutions for n=4
..1..0..2..1..0....2..1..0..2..1....0..2..1..0..2....0..3..0..3..3
..1..2..0..1..2....0..1..2..0..1....2..3..1..2..3....3..2..1..0..2
..0..3..3..0..3....3..0..3..3..0....0..3..0..0..0....2..0..1..2..3
..1..0..2..1..0....2..1..0..2..1....0..2..1..3..2....3..3..0..0..3
..1..2..0..1..2....0..1..2..3..1....2..3..1..2..0....0..2..1..0..2
..0..3..3..0..0....3..0..0..0..3....0..0..0..3..3....2..3..1..2..0
CROSSREFS
Sequence in context: A109564 A188008 A145755 * A339960 A252442 A159625
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 16 2014
STATUS
approved