1,2

Numerators: A120831(n);

A120831(n)/a(n) = Sum(A068318(n)/A001358(n):1<=k<=n).

n=5: (2+2)/2*2+(2+3)/2*3+(3+3)/3*3+(2+5)/2*5+(2+7)/2*7 =

4/4 + 5/6 + 6/9 + 7/10 + 9/14 = 269/70 = A120831(5)/a(5).

Cf. A120835, A120834.

Sequence in context: A010371 A011489 A093601 this_sequence A021988 A021619 A107496

Adjacent sequences: A120829 A120830 A120831 this_sequence A120833 A120834 A120835

nonn,frac

Reinhard Zumkeller (reinhard.zumkeller(AT)lhsystems.com), Jul 24 2006