A252185 Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and column sum equal to 0 1 3 6 or 7 and every 3X3 diagonal and antidiagonal sum not equal to 0 1 3 6 or 7

945, 1440, 2055, 3341, 5300, 7973, 13044, 21238, 32234, 53032, 87440, 133042, 218874, 363938, 553312, 908558, 1520436, 2306990, 3778274, 6356426, 9620954, 15713012, 26556444, 40091976, 65299770, 110813364, 166873308, 271087620

Offset

1,1

Comments

Column 1 of A252192

Links

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

Formula

Empirical: a(n) = -a(n-1) +14*a(n-3) +14*a(n-4) +a(n-5) -76*a(n-6) -77*a(n-7) -13*a(n-8) +199*a(n-9) +212*a(n-10) +65*a(n-11) -243*a(n-12) -308*a(n-13) -159*a(n-14) +65*a(n-15) +224*a(n-16) +202*a(n-17) +138*a(n-18) -64*a(n-19) -128*a(n-20) -128*a(n-21) +32*a(n-23) +32*a(n-24) for n>30

Example

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

Crossrefs

Sequence in context: A125013 A294576 A252192 * A381550 A005231 A174865

Adjacent sequences: A252182 A252183 A252184 * A252186 A252187 A252188

Keyword

nonn

Author

R. H. Hardin, Dec 15 2014

Status

approved