OFFSET
1,3
LINKS
Eric Weisstein's World of Mathematics, Prime sums
FORMULA
a(n) = numerator(Sum_{k=1..n} (-1)^(k+1)/(prime(k)-1)).
MATHEMATICA
Table[Numerator[Sum[(-1)^(k+1)*1/(Prime[k]-1), {k, 1, n}]], {n, 1, 36}]
CROSSREFS
KEYWORD
frac,nonn
AUTHOR
Alexander Adamchuk, Mar 18 2007
STATUS
approved