A252562 Number of (4+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 1 2 4 6 or 7 and every 3X3 column and antidiagonal sum not equal to 1 2 4 6 or 7

1265, 3084, 10585, 24336, 104515, 386004, 902276, 3886119, 14439854, 33740636, 145226515, 541433298, 1264809720, 5437258963, 20326627042, 47472999320, 203838402331, 764011813890, 1783974607832, 7651263017251, 28749096631362

Offset

1,1

Comments

Row 4 of A252558

Links

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

Formula

Empirical: a(n) = 78*a(n-3) -1701*a(n-6) +7656*a(n-9) -30460*a(n-12) +70284*a(n-15) -70416*a(n-18) +25968*a(n-21) -1408*a(n-24) for n>30

Example

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

Crossrefs

Sequence in context: A237327 A233887 A234147 * A364610 A038652 A204720

Adjacent sequences: A252559 A252560 A252561 * A252563 A252564 A252565

Keyword

nonn

Author

R. H. Hardin, Dec 18 2014

Status

approved