A252608 Number of (n+2)X(1+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

614, 725, 1042, 1635, 3022, 5503, 9927, 19165, 36457, 66942, 130253, 250493, 461838, 901547, 1740381, 3212610, 6279191, 12136529, 22411460, 43823953, 84734165, 156496838, 306070623, 591832623, 1093177438, 2138153485, 4134310387

Offset

1,1

Comments

Column 1 of A252615

Links

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

Formula

Empirical: a(n) = 21*a(n-3) +a(n-4) -166*a(n-6) -19*a(n-7) +635*a(n-9) +128*a(n-10) -1321*a(n-12) -379*a(n-13) +1640*a(n-15) +563*a(n-16) -1416*a(n-18) -514*a(n-19) +944*a(n-21) +388*a(n-22) -336*a(n-24) -168*a(n-25) for n>31

Example

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

Crossrefs

Sequence in context: A117503 A165771 A025329 * A252615 A252616 A252607

Adjacent sequences: A252605 A252606 A252607 * A252609 A252610 A252611

Keyword

nonn

Author

R. H. Hardin, Dec 19 2014

Status

approved