A252107 Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and column sum equal to 0 2 3 6 or 7 and every 3X3 diagonal and antidiagonal sum not equal to 0 2 3 6 or 7

1417, 1929, 1568, 1600, 1884, 2058, 2468, 3149, 3950, 5208, 6792, 8716, 11582, 15298, 19912, 26490, 35242, 46364, 61862, 82494, 108984, 145626, 194574, 257870, 344814, 461252, 612860, 819926, 1097602, 1461226, 1955936, 2620002, 3493420, 4678324

Offset

1,1

Comments

Column 1 of A252114

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 7*a(n-3) +2*a(n-5) -18*a(n-6) -11*a(n-8) +20*a(n-9) -a(n-10) +20*a(n-11) -8*a(n-12) +4*a(n-13) -11*a(n-14) -4*a(n-16) -4*a(n-17) -2*a(n-19) +4*a(n-20) +5*a(n-22) -2*a(n-25) for n>33

Example

Some solutions for n=4
..1..2..3....2..1..3....3..1..2....2..3..2....2..3..1....2..3..2....0..1..2
..2..2..2....1..2..3....2..1..3....1..2..0....0..0..2....2..3..2....3..2..2
..0..2..1....0..3..0....2..0..1....0..2..1....0..0..3....3..0..3....0..3..3
..1..2..0....2..1..0....2..1..3....2..2..2....3..2..1....2..3..2....3..2..2
..2..2..2....0..3..0....3..1..2....1..2..3....0..1..2....2..3..2....3..2..2
..3..3..1....1..3..3....1..1..1....0..2..1....3..0..0....3..0..3....1..3..3

Crossrefs

Sequence in context: A237220 A188099 A252106 * A252114 A364125 A293093

Adjacent sequences: A252104 A252105 A252106 * A252108 A252109 A252110

Keyword

nonn

Author

R. H. Hardin, Dec 14 2014

Status

approved