A252561 Number of (3+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

832, 1477, 4006, 8329, 29158, 88899, 189777, 680323, 2097950, 4459797, 16207003, 50241432, 106284365, 390413041, 1215215993, 2560430019, 9487153047, 29626334151, 62221453445, 232146488313, 726802890892, 1522575311063

Offset

1,1

Comments

Row 3 of A252558

Links

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

Formula

Empirical: a(n) = 46*a(n-3) -572*a(n-6) +1298*a(n-9) -3089*a(n-12) +4222*a(n-15) -3472*a(n-18) +3104*a(n-21) -1536*a(n-24) for n>31

Example

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

Crossrefs

Sequence in context: A351666 A045070 A186956 * A264318 A264141 A327604

Adjacent sequences: A252558 A252559 A252560 * A252562 A252563 A252564

Keyword

nonn

Author

R. H. Hardin, Dec 18 2014

Status

approved