A252551 Number of (n+2)X(1+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

771, 747, 832, 1265, 2162, 3761, 6855, 12549, 22875, 42485, 78560, 144498, 269219, 498958, 919276, 1712966, 3176920, 5855198, 10905899, 20234030, 37296589, 69433853, 128861740, 237545254, 442015759, 820561452, 1512757602, 2813618655

Offset

1,1

Comments

Column 1 of A252558

Links

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

Formula

Empirical: a(n) = 26*a(n-3) -280*a(n-6) +1644*a(n-9) -5901*a(n-12) +13891*a(n-15) +9*a(n-16) -22285*a(n-18) -87*a(n-19) +24609*a(n-21) +235*a(n-22) -18285*a(n-24) -174*a(n-25) +8465*a(n-27) -229*a(n-28) -2074*a(n-30) +496*a(n-31) +616*a(n-33) -313*a(n-34) -1069*a(n-36) +38*a(n-37) +983*a(n-39) +40*a(n-40) -355*a(n-42) -17*a(n-43) -37*a(n-45) +2*a(n-46) +72*a(n-48) -21*a(n-51) +2*a(n-54) for n>60

Example

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

Crossrefs

Sequence in context: A236784 A205622 A205357 * A045078 A252550 A252558

Adjacent sequences: A252548 A252549 A252550 * A252552 A252553 A252554

Keyword

nonn

Author

R. H. Hardin, Dec 18 2014

Status

approved