A252418 - OEIS

A252418

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

1099, 1098, 2348, 3796, 11409, 30724, 53782, 173544, 488169, 862550, 2861114, 8190964, 14510150, 48759525, 140792605, 249710691, 844670520, 2449784273, 4347633163, 14756809096, 42898150674, 76155945522, 258954750275

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Column 3 of A252423.

LINKS

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

FORMULA

Empirical: a(n) = 38*a(n-3) -510*a(n-6) +3209*a(n-9) -10762*a(n-12) +20397*a(n-15) -22122*a(n-18) +13410*a(n-21) -4305*a(n-24) +686*a(n-27) -40*a(n-30) for n>37.

EXAMPLE

Some solutions for n=4

..3..0..1..0..3....3..0..1..3..0....0..0..1..0..0....0..1..0..0..3

..1..1..2..1..1....1..1..2..1..1....0..0..1..0..0....2..0..2..2..0

..0..0..1..0..0....0..0..1..0..3....1..1..2..1..1....2..0..2..2..0

..0..0..1..3..0....0..3..1..0..0....0..0..1..3..0....0..3..0..0..3

..1..1..2..1..1....1..1..2..1..1....0..0..1..0..2....1..0..2..2..0

..3..0..1..0..0....3..0..1..0..3....1..1..2..1..1....2..0..2..2..0

CROSSREFS

Cf. A252423.

Sequence in context: A186476 A096926 A249287 * A261911 A276708 A277797

Adjacent sequences: A252415 A252416 A252417 * A252419 A252420 A252421

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 17 2014

STATUS

approved