A252403 Number of (n+2)X(4+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 2 3 4 6 or 7 and every 3X3 column and antidiagonal sum not equal to 2 3 4 6 or 7

1551, 1157, 2555, 6231, 16906, 44456, 113146, 311214, 819606, 2086566, 5746545, 15147605, 38558032, 106198296, 280032267, 712923101, 1963719979, 5179266001, 13187734424, 36328962794, 95838112695, 244064366602, 672411482149

Offset

1,1

Comments

Column 4 of A252407

Links

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

Formula

Empirical: a(n) = 43*a(n-3) -607*a(n-6) +3871*a(n-9) -22906*a(n-12) +87039*a(n-15) -288666*a(n-18) +675828*a(n-21) -1232028*a(n-24) +1513050*a(n-27) -509862*a(n-30) -839791*a(n-33) +309408*a(n-36) +328998*a(n-39) +118167*a(n-42) -74798*a(n-45) -58186*a(n-48) -7379*a(n-51) -1782*a(n-54) -508*a(n-57) +87*a(n-60) +22*a(n-63) +a(n-66) for n>69

Example

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

Crossrefs

Sequence in context: A020408 A259424 A323330 * A252053 A252046 A252045

Adjacent sequences: A252400 A252401 A252402 * A252404 A252405 A252406

Keyword

nonn

Author

R. H. Hardin, Dec 17 2014

Status

approved