A252134 Number of (n+2)X(3+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 3 4 6 or 7.

209, 431, 1535, 5233, 18047, 62277, 213689, 735011, 2535415, 8731891, 30044153, 103433117, 356211269, 1226555379, 4222869347, 14539251441, 50061141877, 172368825649, 593481175735, 2043402198055, 7035653624363, 24224571439391

Offset

1,1

Comments

Column 3 of A252139

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +11*a(n-3) +20*a(n-4) +12*a(n-5) -7*a(n-6) -69*a(n-7) -49*a(n-8) +69*a(n-9) +59*a(n-10) -9*a(n-11) -30*a(n-12) -14*a(n-13) +2*a(n-14) +4*a(n-16) for n>17

Example

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

Crossrefs

Sequence in context: A283742 A083512 A168424 * A063366 A064906 A337778

Adjacent sequences: A252131 A252132 A252133 * A252135 A252136 A252137

Keyword

nonn

Author

R. H. Hardin, Dec 14 2014

Status

approved