A251869 Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and column sum not 2 4 5 or 7 and every diagonal and antidiagonal sum 2 4 5 or 7

1038, 2146, 3092, 5756, 11008, 18400, 32372, 60292, 100612, 176372, 322532, 547244, 957412, 1726428, 2976676, 5237036, 9377508, 16323580, 28791476, 51347308, 90018580, 159196860, 283147012, 498087484, 881978324, 1566542540, 2762581684

Offset

1,1

Comments

Column 1 of A251876

Links

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

Formula

Empirical: a(n) = 11*a(n-3) +6*a(n-5) -38*a(n-6) -58*a(n-8) +18*a(n-9) +208*a(n-11) +160*a(n-12) -328*a(n-14) -328*a(n-15) +192*a(n-17) +192*a(n-18) for n>23

Example

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

Crossrefs

Sequence in context: A159052 A065572 A251876 * A251868 A074673 A235156

Adjacent sequences: A251866 A251867 A251868 * A251870 A251871 A251872

Keyword

nonn

Author

R. H. Hardin, Dec 10 2014

Status

approved