A252437 Number of (4+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

878, 1801, 3954, 7575, 26396, 74892, 151863, 530739, 1491580, 3021857, 10585353, 29761784, 60370995, 211427247, 593997328, 1205792009, 4223479870, 11857758532, 24089996163, 84387563433, 236761731724, 481383227645, 1686474375006

Offset

1,1

Comments

Row 4 of A252433

Links

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

Formula

Empirical: a(n) = 41*a(n-3) -427*a(n-6) -92*a(n-9) +4948*a(n-12) -4734*a(n-15) -16460*a(n-18) +22444*a(n-21) +22257*a(n-24) -37919*a(n-27) -8433*a(n-30) +18472*a(n-33) +420*a(n-36) -516*a(n-39) for n>46

Example

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

Crossrefs

Sequence in context: A208587 A208472 A093943 * A129313 A063051 A190030

Adjacent sequences: A252434 A252435 A252436 * A252438 A252439 A252440

Keyword

nonn

Author

R. H. Hardin, Dec 17 2014

Status

approved