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A251647 Number of (n+2)X(3+2) 0..3 arrays with no row, column, diagonal or antidiagonal in any 3X3 subblock summing to 0 2 4 5 7 or 9 1
738, 1928, 4522, 9918, 31022, 74194, 163318, 509054, 1221194, 2704574, 8386814, 20177362, 44950790, 138592654, 334384234, 749470958, 2296746062, 5557738322, 12535135958, 38171299294, 92650542218, 210319394398, 636286353118 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A251652

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) -2*a(n-2) +10*a(n-3) -60*a(n-4) +34*a(n-5) +95*a(n-6) -64*a(n-7) -32*a(n-8) +16*a(n-9) for n>13

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

CROSSREFS

Sequence in context: A171641 A251814 A320714 * A337738 A204289 A204285

Adjacent sequences:  A251644 A251645 A251646 * A251648 A251649 A251650

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 06 2014

STATUS

approved

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Last modified March 4 05:42 EST 2021. Contains 341779 sequences. (Running on oeis4.)