A251874 - OEIS

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A251874

Number of (n+2)X(6+2) 0..3 arrays with every 3X3 subblock row and column sum not 2 4 5 or 7 and every diagonal and antidiagonal sum 2 4 5 or 7

18400, 41816, 31296, 46464, 151704, 309144, 506656, 1847872, 4274816, 7487600, 26505656, 67284984, 123248320, 462330456, 1240757144, 2319782976, 8747007608, 24156027576, 45628433856, 175122465816, 489988794200, 928931023680

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Column 6 of A251876

LINKS

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

FORMULA

Empirical: a(n) = 34*a(n-3) -193*a(n-6) -2720*a(n-9) +20816*a(n-12) +34816*a(n-15) -279552*a(n-18) for n>28

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

CROSSREFS

Sequence in context: A203783 A071368 A231142 * A035924 A375908 A209895

Adjacent sequences: A251871 A251872 A251873 * A251875 A251876 A251877

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 10 2014

STATUS

approved