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A209824
Number of (n+1)X4 0..2 arrays with every 2X2 subblock having one or two distinct values, and new values 0..2 introduced in row major order
1
218, 4418, 90000, 1842509, 37744836, 773359089, 15846003427, 324684577671, 6652797311199, 136316077450664, 2793121983572647, 57231184269590694, 1172669322792974754, 24028042740488215416, 492335585844232823766
OFFSET
1,1
COMMENTS
Column 3 of A209829
LINKS
FORMULA
Empirical: a(n) = 24*a(n-1) -62*a(n-2) -226*a(n-3) +445*a(n-4) +475*a(n-5) -811*a(n-6) +29*a(n-7) +147*a(n-8) -20*a(n-9)
EXAMPLE
Some solutions for n=4
..0..1..0..1....0..0..1..0....0..0..0..1....0..1..0..0....0..0..0..0
..1..0..0..0....0..1..1..1....2..2..0..0....0..1..0..0....0..1..0..0
..1..0..2..2....0..0..1..2....1..2..0..1....0..1..0..2....0..0..0..2
..1..0..2..1....2..0..1..1....2..2..0..0....0..0..0..2....0..0..2..2
..1..0..2..1....2..0..0..1....0..2..2..0....2..0..0..2....0..2..2..1
CROSSREFS
Sequence in context: A253732 A232513 A224741 * A230333 A060530 A252997
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 13 2012
STATUS
approved