A251872 Number of (n+2)X(4+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

5756, 15116, 9936, 13152, 31520, 46464, 62720, 164480, 252736, 389376, 910400, 1559552, 2443264, 5882368, 10571776, 17743872, 40570880, 77176832, 131203072, 302153728, 586940416, 1020788736, 2313420800, 4577165312, 7994343424

Offset

1,1

Comments

Column 4 of A251876

Links

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

Formula

Empirical: a(n) = 8*a(n-3) +16*a(n-6) -128*a(n-9) for n>17

Example

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

Crossrefs

Sequence in context: A218048 A202419 A076426 * A190466 A157988 A330343

Adjacent sequences: A251869 A251870 A251871 * A251873 A251874 A251875

Keyword

nonn

Author

R. H. Hardin, Dec 10 2014

Status

approved