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A252251 Number of (n+2) X (5+2) 0..3 arrays with every 3 X 3 subblock row and column sum not equal to 0 3 5 6 or 7 and every 3 X 3 diagonal and antidiagonal sum equal to 0 3 5 6 or 7. 1
463, 302, 279, 297, 327, 366, 414, 492, 594, 720, 924, 1191, 1521, 2055, 2754, 3618, 5016, 6846, 9108, 12768, 17559, 23481, 33063, 45606, 61110, 86196, 119034, 159624, 225300, 311271, 417537, 589479, 814554, 1092762, 1542912, 2132166, 2860524 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) + 3*a(n-3) - 3*a(n-4) - a(n-6) + a(n-7) for n>9.

Empirical g.f.: x*(463 - 161*x - 23*x^2 - 1371*x^3 + 513*x^4 + 108*x^5 + 457*x^6 - 173*x^7 - 38*x^8) / ((1 - x)*(1 - 3*x^3 + x^6)). - Colin Barker, Dec 02 2018

EXAMPLE

Some solutions for n=4:

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

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

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

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

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

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

CROSSREFS

Column 5 of A252254.

Sequence in context: A028684 A212928 A102997 * A139662 A140030 A020371

Adjacent sequences:  A252248 A252249 A252250 * A252252 A252253 A252254

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 16 2014

STATUS

approved

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Last modified October 16 16:20 EDT 2021. Contains 348042 sequences. (Running on oeis4.)