OFFSET
0,4
COMMENTS
FORMULA
MATHEMATICA
max = 25; A001803 = CoefficientList[Series[(1 - x)^(-3/2), {x, 0, max}], x] // Numerator; A001790 = CoefficientList[Series[1/Sqrt[(1 - x)], {x, 0, max}], x] // Numerator; A046161 = Table[Binomial[2 n, n]/4^n, {n, 0, max}] // Denominator; a[0] = 1; a[n_] := (A001803[[n]] + A001790[[n]])/(2*A046161[[n]]) // Denominator; Table[a[n], {n, 0, max}]
(* or, directly: *) a[0] = 1; a[n_] := Denominator[4^(1-n)*Binomial[2*n-2, n-1]]/2^IntegerExponent[n, 2]; Table[a[n], {n, 0, max}]
CROSSREFS
KEYWORD
nonn,frac
AUTHOR
Jean-François Alcover and Paul Curtz, Nov 06 2013
STATUS
approved