A252568 Number of (n+2)X(2+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 1 2 5 6 or 7 and every 3X3 column and antidiagonal sum not equal to 1 2 5 6 or 7

843, 868, 1558, 3286, 7610, 17261, 39419, 94224, 218717, 504824, 1216914, 2842764, 6585725, 15930113, 37308440, 86581201, 209741403, 491769283, 1142254876, 2768731230, 6494985545, 15093638282, 36592496037, 85859457999, 199589766685

Offset

1,1

Comments

Column 2 of A252574

Links

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

Formula

Empirical: a(n) = 41*a(n-3) -642*a(n-6) +4961*a(n-9) -21249*a(n-12) +55203*a(n-15) -94450*a(n-18) +115159*a(n-21) -104947*a(n-24) +71287*a(n-27) -34926*a(n-30) +11911*a(n-33) -2699*a(n-36) +381*a(n-39) -30*a(n-42) +a(n-45) for n>50

Example

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

Crossrefs

Sequence in context: A154473 A093242 A031527 * A045243 A368778 A096025

Adjacent sequences: A252565 A252566 A252567 * A252569 A252570 A252571

Keyword

nonn

Author

R. H. Hardin, Dec 18 2014

Status

approved