OFFSET
0,3
FORMULA
a(n) = 2^(e_2((2*n)!)-n)/n! * Product[8k+1,{k,0,n-1}] where e_2((2n)!) is the highest power of 2 that divides (2*n)! (sequence A005187)
MATHEMATICA
w[n_] := Numerator[Binomial[(-1/8, n](-1)^n]
Table[w1[n], {n, 0, 12}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Emanuele Munarini, Jan 25 2011
STATUS
approved