A252186 - OEIS

A252186

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

1440, 1886, 2610, 3996, 6368, 9508, 15094, 24092, 36352, 58610, 94310, 142892, 231354, 373418, 566836, 919562, 1486322, 2258180, 3666858, 5930882, 9014692, 14644970, 23695010, 36023012, 58535274, 94723298, 144020836, 234052202

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

OFFSET

1,1

COMMENTS

Column 2 of A252192.

LINKS

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

FORMULA

Empirical: a(n) = 7*a(n-3) -14*a(n-6) +8*a(n-9) for n>16.

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

CROSSREFS

Cf. A252192.

Sequence in context: A101998 A174277 A063846 * A179691 A078095 A157508

Adjacent sequences: A252183 A252184 A252185 * A252187 A252188 A252189

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 15 2014

STATUS

approved