A252124 Number of (n+2)X(2+2) 0..3 arrays with every 3X3 subblock row and column sum not equal to 0 3 4 6 or 7 and every 3X3 diagonal and antidiagonal sum equal to 0 3 4 6 or 7

634, 1732, 5622, 10379, 34891, 120600, 218388, 776527, 2785875, 4949307, 18191635, 66629582, 116701535, 437583275, 1622139182, 2811915708, 10676440663, 39872706809, 68597203451, 262614612215, 985534471328, 1686109541499

Offset

1,1

Comments

Column 2 of A252130

Links

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

Formula

Empirical: a(n) = a(n-1) +73*a(n-3) -73*a(n-4) -2065*a(n-6) +2065*a(n-7) +29083*a(n-9) -29083*a(n-10) -218284*a(n-12) +218284*a(n-13) +853720*a(n-15) -853720*a(n-16) -1434309*a(n-18) +1434309*a(n-19) -512391*a(n-21) +512391*a(n-22) +5300937*a(n-24) -5300937*a(n-25) -6791661*a(n-27) +6791661*a(n-28) +3067146*a(n-30) -3067146*a(n-31) -437400*a(n-33) +437400*a(n-34) for n>37

Example

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

Crossrefs

Sequence in context: A074762 A177684 A177214 * A112137 A260244 A250581

Adjacent sequences: A252121 A252122 A252123 * A252125 A252126 A252127

Keyword

nonn

Author

R. H. Hardin, Dec 14 2014

Status

approved