Denominator of 2*Sum(C(n,w)/(2*w+1),w=0..n/2-1)+C(n,n/2)/(n+1) if n is even, or of 2*Sum(C(n,w)/(2*w+1),w=0..(n-1)/2) if n is odd.
A085569
Denominator of 2*Sum(C(n,w)/(2*w+1),w=0..n/2-1)+C(n,n/2)/(n+1) if n is even, or of 2*Sum(C(n,w)/(2*w+1),w=0..(n-1)/2) if n is odd.
Terms
- a(0) =1a(1) =1a(2) =3a(3) =1a(4) =15a(5) =3a(6) =7a(7) =15a(8) =45a(9) =5a(10) =231a(11) =21a(12) =455a(13) =315a(14) =45a(15) =3a(16) =1683a(17) =3465a(18) =7315a(19) =5005a(20) =3003a(21) =143a(22) =13455a(23) =585a(24) =6825a(25) =13923a(26) =3213a(27) =6545a(28) =515185a(29) =17765
External references
- oeis: A085569