A252099 Number of (n+2)X(2+2) 0..3 arrays with every 3X3 subblock row and column sum equal to 0 3 4 6 or 7 and every 3X3 diagonal and antidiagonal sum not equal to 0 3 4 6 or 7

4581, 4866, 5087, 8941, 21405, 50222, 120128, 312242, 762514, 1878978, 4952226, 12363575, 31123465, 82567495, 210479834, 540052088, 1440608932, 3742122672, 9761698780, 26154115812, 69025530491, 182512931249, 490665213507

Offset

1,1

Comments

Column 2 of A252105

Links

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

Formula

Empirical: a(n) = 69*a(n-3) -1953*a(n-6) +29920*a(n-9) +36*a(n-11) -278255*a(n-12) -1940*a(n-14) +1692745*a(n-15) +40112*a(n-17) -7161794*a(n-18) -420060*a(n-20) +22075677*a(n-21) +2500924*a(n-23) -50523975*a(n-24) -8983544*a(n-26) +84503984*a(n-27) +20012284*a(n-29) -98978713*a(n-30) -27763500*a(n-32) +76679663*a(n-33) +23593520*a(n-35) -36673389*a(n-36) -11815076*a(n-38) +9873702*a(n-39) +3248004*a(n-41) -1302480*a(n-42) -432360*a(n-44) +64800*a(n-45) +21600*a(n-47) for n>53

Example

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

Crossrefs

Sequence in context: A234677 A252063 A068756 * A252405 A252580 A230947

Adjacent sequences: A252096 A252097 A252098 * A252100 A252101 A252102

Keyword

nonn

Author

R. H. Hardin, Dec 14 2014

Status

approved