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A252156 Number of (n+2)X(7+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
13146, 16786, 35924, 58792, 114243, 223442, 446661, 897932, 1788360, 3551084, 7203948, 14236172, 28512252, 57373724, 114332028, 227108060, 460814748, 910763612, 1824282396, 3671115932, 7315999260, 14533069724, 29489106588 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A252157

LINKS

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

FORMULA

Empirical: a(n) = -a(n-1) +2*a(n-2) +14*a(n-3) +14*a(n-4) -28*a(n-5) -56*a(n-6) -56*a(n-7) +112*a(n-8) +64*a(n-9) +64*a(n-10) -128*a(n-11) for n>16

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

CROSSREFS

Sequence in context: A206149 A221156 A068760 * A102331 A064252 A252590

Adjacent sequences:  A252153 A252154 A252155 * A252157 A252158 A252159

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 14 2014

STATUS

approved

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Last modified August 12 09:05 EDT 2020. Contains 336438 sequences. (Running on oeis4.)