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A209380
1/4 the number of (n+1)X7 0..2 arrays with every 2X2 subblock having distinct edge sums
1
128, 410, 840, 4004, 8648, 52784, 114056, 790712, 1693448, 12487208, 26563080, 201742280, 427484168, 3292956296, 6963468296, 54006743816, 114088980488, 887752094216, 1874426109960, 14608478297096, 30837161410568
OFFSET
1,1
COMMENTS
Column 6 of A209382
LINKS
FORMULA
Empirical: a(n) = a(n-1) +38*a(n-2) -38*a(n-3) -516*a(n-4) +516*a(n-5) +3144*a(n-6) -3144*a(n-7) -8480*a(n-8) +8480*a(n-9) +7936*a(n-10) -7936*a(n-11)
EXAMPLE
Some solutions for n=4
..2..0..0..1..0..0..2....0..1..0..2..2..2..2....2..2..0..2..2..1..2
..2..1..2..2..2..1..2....2..2..0..1..0..1..0....0..1..0..1..0..0..2
..2..0..0..1..0..0..0....0..1..0..2..2..2..2....2..2..0..2..2..1..2
..2..1..2..2..2..1..2....0..2..0..1..0..1..0....0..1..0..1..0..0..2
..0..0..0..1..0..0..2....0..1..0..2..2..2..2....2..2..2..2..2..1..2
CROSSREFS
Sequence in context: A220582 A203449 A195090 * A135271 A369638 A223316
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 07 2012
STATUS
approved