A251887 Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and column sum not 2 3 6 or 7 and every diagonal and antidiagonal sum 2 3 6 or 7

1280, 1664, 1280, 1280, 1534, 1752, 2146, 2838, 3446, 4406, 5830, 7266, 9446, 12606, 15958, 20914, 27986, 35746, 47062, 62958, 80926, 106810, 142678, 184318, 243594, 324870, 421406, 557302, 742186, 966026, 1277974, 1699954, 2219006, 2936010

Offset

1,1

Comments

Column 1 of A251894

Links

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

Formula

Empirical: a(n) = 5*a(n-3) +a(n-5) -8*a(n-6) -4*a(n-8) +4*a(n-9) +5*a(n-11) -2*a(n-14) for n>22

Example

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

Crossrefs

Sequence in context: A251886 A234137 A160233 * A251894 A251791 A251784

Adjacent sequences: A251884 A251885 A251886 * A251888 A251889 A251890

Keyword

nonn

Author

R. H. Hardin, Dec 10 2014

Status

approved