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A252675
Number of (n+2)X(4+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 2 5 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 2 5 6 or 7
1
1246, 1525, 3424, 7747, 22203, 56318, 136414, 396057, 1018638, 2491848, 7256099, 18740823, 45930118, 133764096, 345973229, 848474793, 2470203352, 6393928103, 15686518177, 45650583739, 118239174725, 290168205360, 844090916262
OFFSET
1,1
COMMENTS
Column 4 of A252679
LINKS
FORMULA
Empirical: a(n) = 47*a(n-3) -779*a(n-6) +6299*a(n-9) -38390*a(n-12) +178663*a(n-15) -636822*a(n-18) +1830492*a(n-21) -3935340*a(n-24) +6441162*a(n-27) -6562062*a(n-30) +1199657*a(n-33) +3668572*a(n-36) -908634*a(n-39) -1197825*a(n-42) -547466*a(n-45) +241006*a(n-48) +225365*a(n-51) +27734*a(n-54) +6620*a(n-57) +2119*a(n-60) -326*a(n-63) -87*a(n-66) -4*a(n-69) for n>71
EXAMPLE
Some solutions for n=4
..0..1..1..0..1..1....1..1..3..1..1..0....1..0..1..1..0..1....1..1..3..1..1..0
..1..0..1..1..0..1....2..0..0..2..0..0....1..1..3..1..1..3....2..0..0..2..3..0
..3..0..2..3..0..2....1..0..1..1..0..1....2..0..0..2..0..0....1..0..1..1..0..1
..0..1..1..0..1..1....1..1..0..1..1..0....1..3..1..1..0..1....1..1..0..1..1..0
..1..0..1..1..0..1....2..0..3..2..0..0....1..1..0..1..1..3....2..0..0..2..0..3
..3..0..2..0..3..2....1..0..1..1..3..1....2..0..0..2..0..0....1..0..1..1..3..1
CROSSREFS
Sequence in context: A023065 A375801 A190413 * A066696 A195006 A114528
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 20 2014
STATUS
approved