This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A120834 #4 Mar 30 2012 18:50:54 %S A120834 1,5,10,70,630,2520,2520,32760,32760,32760,32760,622440,622440,622440, %T A120834 1244880,6224400,6224400,6224400,1556100,17117100,530630100,530630100, %U A120834 176876700,176876700,176876700 %N A120834 Denominators of partial sums of (p+q)/p*q, where p and q are primes. %C A120834 Numerators: A120833(n); %C A120834 A120833(n)/a(n) = Sum(A001358(n)/A068318(n):1<=k<=n). %e A120834 n=5: 2*2/(2+2)+2*3/(2+3)+3*3/(3+3)+2*5/(2+5)+2*7/(2+7) = %e A120834 4/4 + 6/5 + 9/6 + 10/7 + 14/9 = 4211/630 = A120833(5)/a(5). %Y A120834 Cf. A120836, A120832. %K A120834 nonn,frac %O A120834 1,2 %A A120834 _Reinhard Zumkeller_, Jul 24 2006