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A241806
Two-colorings of triangular arrays under rotational symmetries.
0
1, 2, 4, 24, 352, 10944, 699136, 89479168, 22906494976, 11728124051456, 22906494976, 11728124051456, 12009599006670848, 24595658764948865024, 100743818301219142631424, 825293359523586851364405248, 13521606402434446949321074016256
OFFSET
1,2
MAPLE
Q:= proc(n)
if n mod 3 = 1 then 1/3*2^(1/2*n*(n + 1)) + 1/3*2^(2 + 1/6*(n - 1)*(n + 2))
else 1/3*2^(1/2*n*(n + 1)) + 1/3*2^(1 + 1/6*n*(n + 1))
end if
end proc
CROSSREFS
Sequence in context: A047677 A030276 A081476 * A009273 A332539 A296787
KEYWORD
nonn
AUTHOR
Marko Riedel, Apr 28 2014
STATUS
approved