A252636 Number of (n+2)X(4+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 3 4 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 3 4 6 or 7

3162, 8253, 29463, 95904, 395940, 1504636, 5124134, 21431528, 82893234, 292817550, 1230551308, 4802902204, 17419191296, 73465113332, 288429221652, 1065039430488, 4502736844068, 17743381508580, 66283907402424

Offset

1,1

Comments

Column 4 of A252640

Links

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

Formula

Empirical: a(n) = 145*a(n-3) -7116*a(n-6) +136668*a(n-9) -902360*a(n-12) +4683424*a(n-15) -17197984*a(n-18) +26472832*a(n-21) -12749824*a(n-24) +720896*a(n-27) for n>35

Example

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

Crossrefs

Sequence in context: A184452 A151750 A031610 * A324678 A068266 A140350

Adjacent sequences: A252633 A252634 A252635 * A252637 A252638 A252639

Keyword

nonn

Author

R. H. Hardin, Dec 19 2014

Status

approved