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A251870 Number of (n+2)X(2+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 1
2146, 5632, 7160, 15116, 36852, 41816, 99808, 169196, 246152, 568040, 969972, 1827696, 3266080, 5533228, 11336584, 20569704, 40514260, 75022128, 125003744, 253497484, 485341704, 914789992, 1783429620, 3100407280, 5803394208 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A251876

LINKS

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

FORMULA

Empirical: a(n) = 17*a(n-3) +16*a(n-5) -95*a(n-6) -272*a(n-8) +59*a(n-9) +1776*a(n-11) +1448*a(n-12) -5296*a(n-14) -5812*a(n-15) +5248*a(n-17) +6720*a(n-18) +8256*a(n-20) +7296*a(n-21) -23552*a(n-23) -23552*a(n-24) +15360*a(n-26) +15360*a(n-27) for n>33

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

CROSSREFS

Sequence in context: A259413 A294751 A251893 * A291135 A251852 A251846

Adjacent sequences:  A251867 A251868 A251869 * A251871 A251872 A251873

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 10 2014

STATUS

approved

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Last modified May 22 04:12 EDT 2022. Contains 353933 sequences. (Running on oeis4.)