Denominators of coefficients in (1+x)^(1+x) power series.

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =3a(5) =12a(6) =40a(7) =120a(8) =2520a(9) =5040a(10) =10080a(11) =5040a(12) =19958400a(13) =19958400a(14) =259459200a(15) =518918400a(16) =2179457280a(17) =4358914560