|
%I #5 Oct 07 2012 12:35:02
%S 1,3,13,113,2861,709,45601,408809,49595489,2426258561,485934733,
%T 485460413,2429223061,2427480661,1284905668069,217047437215261,
%U 182605590283392901,36508279615059377,36518889897389297
%N Numerator of Sum[ (-1)^(k-1) * 1/(Prime[k]-1)^2, {k,1,n}].
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PrimeSums.html">Prime Sums</a>.
%F a(n) = numerator[ Sum[ (-1)^(k-1) * 1/(Prime[k]-1)^2, {k,1,n}]].
%t Numerator[Table[Sum[(-1)^(i-1)*1/(Prime[i]-1)^2, {i, 1, n}], {n, 1, 30}]]
%Y Cf. A119686, A006093, A000040, A086242.
%K frac,nonn
%O 1,2
%A _Alexander Adamchuk_, Jun 13 2006
|
