Numerator 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).

A085571

Numerator 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) =2a(1) =6a(2) =11a(3) =20a(4) =101a(5) =175a(6) =593a(7) =173a(8) =1502a(9) =2684a(10) =28649a(11) =52169a(12) =662393a(13) =1224077a(14) =4506259a(15) =4210067a(16) =23506871a(17) =44294491a(18) =41572193a(19) =78849257a(20) =1639049932a(21) =3125022742a(22) =23750582143a(23) =9095291663a(24) =225666905951a(25) =144544431373a(26) =276913262539a(27) =76244134117a(28) =732674442397

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