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A183715
1/20 of the number of (n+1) X 6 0..4 arrays with every 2X2 subblock strictly increasing clockwise or counterclockwise with one decrease.
1
70, 559, 4012, 30113, 224640, 1683197, 12606120, 94463507, 707826798, 5304230928, 39748015308, 297860692491, 2232084261366, 16726639262465, 125344918169856, 939301219166473, 7038871324696794, 52747415646208987, 395274995490521924
OFFSET
1,1
COMMENTS
Column 5 of A183719.
LINKS
FORMULA
Empirical: a(n)=2*a(n-1)+54*a(n-2)-2*a(n-3)-738*a(n-4)-312*a(n-5)+4078*a(n-6)+2098*a(n-7)-10802*a(n-8)-4874*a(n-9)+14854*a(n-10)+4874*a(n-11)-10802*a(n-12)-2098*a(n-13)+4078*a(n-14)+312*a(n-15)-738*a(n-16)+2*a(n-17)+54*a(n-18)-2*a(n-19)-a(n-20).
EXAMPLE
Some solutions for 3 X 6:
..3..1..3..2..3..1....0..2..0..1..4..0....2..3..1..2..1..2....1..0..2..1..2..1
..4..0..4..1..4..0....4..3..4..2..3..1....0..4..0..3..0..4....3..4..3..4..3..4
..2..1..3..2..3..2....1..2..0..1..4..0....2..3..1..2..1..2....2..1..2..0..2..1
...
...L..R..L..R..L.......R..L..R..L..R.......R..L..R..L..R.......L..R..L..R..L...
...R..L..R..L..R.......L..R..L..R..L.......L..R..L..R..L.......R..L..R..L..R...
CROSSREFS
Sequence in context: A235302 A229576 A234556 * A376207 A104475 A169712
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 06 2011
STATUS
approved