Denominator of 2*Sum(C(n,w)/w,w=1..n/2-1)+C(n, n/2)/(n/2) if n is even otherwise of 2*Sum(C(n,w)/w,w=1..(n-1)/2).

A085572

Denominator of 2*Sum(C(n,w)/w,w=1..n/2-1)+C(n, n/2)/(n/2) if n is even otherwise of 2*Sum(C(n,w)/w,w=1..(n-1)/2).

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =3a(5) =3a(6) =6a(7) =1a(8) =5a(9) =5a(10) =30a(11) =30a(12) =210a(13) =210a(14) =420a(15) =210a(16) =630a(17) =630a(18) =315a(19) =315a(20) =3465a(21) =3465a(22) =13860a(23) =2772a(24) =36036a(25) =12012a(26) =12012a(27) =1716a(28) =8580a(29) =8580

External references