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A252420 Number of (n+2)X(5+2) 0..3 arrays with every 3X3 subblock row and column sum not equal to 0 2 5 6 or 7 and every 3X3 diagonal and antidiagonal sum equal to 0 2 5 6 or 7 1
2380, 3472, 11409, 22038, 96549, 365974, 715123, 3213732, 12306520, 23990357, 108709726, 418711825, 816544950, 3711392749, 14333000180, 27958629647, 127259409020, 492098163036, 960046258237, 4372912001964, 16920554524983 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A252423

LINKS

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

FORMULA

Empirical: a(n) = 76*a(n-3) -2082*a(n-6) +27585*a(n-9) -201704*a(n-12) +870200*a(n-15) -2284208*a(n-18) +3690384*a(n-21) -3708548*a(n-24) +2399781*a(n-27) -1049128*a(n-30) +305470*a(n-33) -52269*a(n-36) +4604*a(n-39) -160*a(n-42) for n>47

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

CROSSREFS

Sequence in context: A069300 A255800 A252469 * A234818 A107530 A020394

Adjacent sequences:  A252417 A252418 A252419 * A252421 A252422 A252423

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 17 2014

STATUS

approved

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Last modified May 18 23:31 EDT 2022. Contains 353826 sequences. (Running on oeis4.)