A251775 Number of (n+2)X(4+2) 0..3 arrays with every 3X3 subblock row and column sum 3 or 6 and every diagonal and antidiagonal sum not 3 or 6

4790, 34934, 144818, 524774, 3849230, 16580426, 60326174, 447979046, 1931849642, 7044376358, 52367746670, 225917404970, 823970129438, 6126491803910, 26431112366090, 96403314882278, 716807227554830, 3092492752787210

Offset

1,1

Comments

Column 4 of A251779

Links

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

Formula

Empirical: a(n) = a(n-1) +146*a(n-3) -146*a(n-4) -3605*a(n-6) +3605*a(n-7) +24400*a(n-9) -24400*a(n-10) +61000*a(n-12) -61000*a(n-13) -1184000*a(n-15) +1184000*a(n-16) +3392000*a(n-18) -3392000*a(n-19) -1024000*a(n-21) +1024000*a(n-22)

Example

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

Crossrefs

Sequence in context: A354086 A380348 A296812 * A096517 A221005 A227495

Adjacent sequences: A251772 A251773 A251774 * A251776 A251777 A251778

Keyword

nonn

Author

R. H. Hardin, Dec 08 2014

Status

approved