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A252618
Number of (3+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 3 5 6 or 8 and every 3X3 column and antidiagonal sum not equal to 0 3 5 6 or 8
1
1042, 2817, 7031, 17762, 58239, 156499, 437805, 1506801, 4136820, 11865455, 41976597, 116407007, 337378745, 1211267119, 3374947162, 9828010763, 35545348591, 99260624406, 289689365514, 1051432471689, 2939191705954
OFFSET
1,1
COMMENTS
Row 3 of A252615
LINKS
FORMULA
Empirical: a(n) = 64*a(n-3) -1475*a(n-6) +16806*a(n-9) -109891*a(n-12) +449148*a(n-15) -1217688*a(n-18) +2303890*a(n-21) -3171129*a(n-24) +3207942*a(n-27) -2291813*a(n-30) +1076912*a(n-33) -308227*a(n-36) +49142*a(n-39) -3776*a(n-42) +96*a(n-45) for n>48
EXAMPLE
Some solutions for n=4
..1..2..0..3..2..0....0..3..3..2..3..3....2..3..3..2..0..3....0..0..3..2..3..0
..0..3..2..3..0..2....0..2..3..3..2..0....2..1..2..2..1..2....0..2..3..3..2..3
..1..2..2..1..2..2....2..2..1..2..2..1....3..0..2..3..0..2....2..2..1..2..2..1
..0..2..3..3..2..3....2..0..3..2..3..0....2..0..3..2..0..3....2..3..3..2..3..0
..0..3..2..3..3..2....3..2..3..3..2..3....2..1..2..2..2..2....3..2..3..3..2..3
CROSSREFS
Sequence in context: A233854 A168412 A183742 * A231112 A213811 A260205
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 19 2014
STATUS
approved