OFFSET
1,2
FORMULA
a(1) = 1; a(n) = a(n-1) + prime(a(n-1)).
EXAMPLE
a(4)=27 because a(3)=8, prime(8)=19 and 8+19=27.
MATHEMATICA
se={1}; a=1; Do[b=a+Prime[a]; se=Append[se, b]; a=b, {i, 13}]; se
NestList[ Prime@# + # &, 1, 14] (* Robert G. Wilson v, Jul 17 2010 *)
CROSSREFS
KEYWORD
nonn,changed
AUTHOR
Zak Seidov, Sep 21 2002
EXTENSIONS
a(15) from Robert G. Wilson v, Jul 17 2010
a(16)-a(18) from Charles R Greathouse IV, Mar 15 2011
STATUS
approved