A252619 Number of (4+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

1635, 5304, 15119, 43595, 147592, 433665, 1358948, 4510703, 13168210, 41784191, 138318568, 403291980, 1282563188, 4244649464, 12367849652, 39358997579, 130295588917, 379413675833, 1207890310364, 4000234488188, 11641349806833

Offset

1,1

Comments

Row 4 of A252615

Links

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

Formula

Empirical: a(n) = 87*a(n-3) -2807*a(n-6) +43901*a(n-9) -398524*a(n-12) +2360470*a(n-15) -9915211*a(n-18) +31252617*a(n-21) -75900949*a(n-24) +141692395*a(n-27) -198619746*a(n-30) +202498624*a(n-33) -145833984*a(n-36) +72479094*a(n-39) -24333174*a(n-42) +5351052*a(n-45) -726164*a(n-48) +53920*a(n-51) -1600*a(n-54) for n>58

Example

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

Crossrefs

Sequence in context: A219007 A072409 A052455 * A224461 A233121 A054808

Adjacent sequences: A252616 A252617 A252618 * A252620 A252621 A252622

Keyword

nonn

Author

R. H. Hardin, Dec 19 2014

Status

approved