A252156 Number of (n+2)X(7+2) 0..3 arrays with every 3X3 subblock row and column sum not equal to 0 1 3 6 or 7 and every 3X3 diagonal and antidiagonal sum equal to 0 1 3 6 or 7

13146, 16786, 35924, 58792, 114243, 223442, 446661, 897932, 1788360, 3551084, 7203948, 14236172, 28512252, 57373724, 114332028, 227108060, 460814748, 910763612, 1824282396, 3671115932, 7315999260, 14533069724, 29489106588

Offset

1,1

Comments

Column 7 of A252157

Links

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

Formula

Empirical: a(n) = -a(n-1) +2*a(n-2) +14*a(n-3) +14*a(n-4) -28*a(n-5) -56*a(n-6) -56*a(n-7) +112*a(n-8) +64*a(n-9) +64*a(n-10) -128*a(n-11) for n>16

Example

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

Crossrefs

Sequence in context: A206149 A221156 A068760 * A102331 A064252 A252590

Adjacent sequences: A252153 A252154 A252155 * A252157 A252158 A252159

Keyword

nonn

Author

R. H. Hardin, Dec 14 2014

Status

approved