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A252152 Number of (n+2)X(3+2) 0..3 arrays with every 3X3 subblock row and column sum not equal to 0 1 3 6 or 7 and every 3X3 diagonal and antidiagonal sum equal to 0 1 3 6 or 7 1
2591, 1898, 3197, 4988, 9572, 17803, 35924, 68613, 140294, 268864, 553258, 1064524, 2194400, 4229940, 8737784, 16851232, 34844104, 67252048, 139112864, 268589808, 555851264, 1073324704, 2221749568, 4290919264, 8882898080, 17157089760 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A252157

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +4*a(n-2) +2*a(n-3) -6*a(n-4) -24*a(n-5) +16*a(n-6) +8*a(n-7) +32*a(n-8) -32*a(n-9) for n>14

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

CROSSREFS

Sequence in context: A252310 A236351 A250241 * A035894 A179702 A258728

Adjacent sequences:  A252149 A252150 A252151 * A252153 A252154 A252155

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 14 2014

STATUS

approved

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Last modified July 6 23:56 EDT 2020. Contains 335484 sequences. (Running on oeis4.)