A251840 Number of (n+2)X(3+2) 0..3 arrays with every 3X3 subblock row and column sum nonprime and every diagonal and antidiagonal sum prime

641, 828, 1803, 2890, 8582, 21748, 40492, 128431, 339592, 639794, 2087597, 5632271, 10609658, 35199882, 96069006, 180868454, 605781397, 1663988392, 3131743910, 10543905961, 29063878897, 54690404276, 184648426284, 509929622436

Offset

1,1

Comments

Column 3 of A251845

Links

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

Formula

Empirical: a(n) = 32*a(n-3) -310*a(n-6) +1096*a(n-9) -1790*a(n-12) +1558*a(n-15) -803*a(n-18) +238*a(n-21) -20*a(n-24) for n>33

Example

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

Crossrefs

Sequence in context: A256777 A252425 A160203 * A252433 A252434 A105130

Adjacent sequences: A251837 A251838 A251839 * A251841 A251842 A251843

Keyword

nonn

Author

R. H. Hardin, Dec 09 2014

Status

approved