A107325 a(n) = ceiling(A063655(n)/2).

1, 2, 2, 2, 3, 3, 4, 3, 3, 4, 6, 4, 7, 5, 4, 4, 9, 5, 10, 5, 5, 7, 12, 5, 5, 8, 6, 6, 15, 6, 16, 6, 7, 10, 6, 6, 19, 11, 8, 7, 21, 7, 22, 8, 7, 13, 24, 7, 7, 8, 10, 9, 27, 8, 8, 8, 11, 16, 30, 8, 31, 17, 8, 8, 9, 9, 34, 11, 13, 9, 36, 9, 37, 20, 10, 12, 9, 10, 40, 9, 9, 22, 42, 10, 11, 23, 16

Offset: 1

Author

Leroy Quet, May 21 2005

Keywords

• nonn

Comments

a(n) is average (rounded up) of middle divisor(s) of n.

Programs

Mathematica

Do[l = Divisors[n]; k = Length[l]; If[EvenQ[k], m = (l[[k/2]] + l[[k/2 + 1]])/2, m = l[[(k+1)/2]]]; Print[Ceiling[m]], {n, 1, 100}] (* Ryan Propper, Sep 17 2005 *)

Extensions

More terms from Ryan Propper, Sep 17 2005