A252439 Number of (6+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 2 4 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 2 4 6 or 7

1603, 6164, 24024, 53028, 284379, 1190037, 2718502, 14673858, 60822070, 140120224, 759992540, 3151322013, 7307890607, 39819735578, 165035172520, 384707477228, 2103912540224, 8717078161415, 20403395380987, 111904137843930

Offset

1,1

Comments

Row 6 of A252433

Links

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

Formula

Empirical: a(n) = 95*a(n-3) -2139*a(n-6) -7409*a(n-9) +194956*a(n-12) +60848*a(n-15) -7025702*a(n-18) +7788378*a(n-21) +119742541*a(n-24) -273713371*a(n-27) -671051999*a(n-30) +2708582795*a(n-33) -2329474380*a(n-36) -526768608*a(n-39) +1416261076*a(n-42) -328618104*a(n-45) -188072944*a(n-48) +71753184*a(n-51) +2455488*a(n-54) -2353536*a(n-57) +248832*a(n-60) for n>67

Example

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

Crossrefs

Sequence in context: A202774 A293370 A352092 * A224949 A171466 A205267

Adjacent sequences: A252436 A252437 A252438 * A252440 A252441 A252442

Keyword

nonn

Author

R. H. Hardin, Dec 17 2014

Status

approved