OFFSET
0,2
COMMENTS
a(n) = A088860(n) for n>=1. - G. C. Greubel, Apr 23 2017
LINKS
FORMULA
a(n) = if n=0 then 1 else 2*A002110(n).
MATHEMATICA
Join[{1}, 2 Denominator[Accumulate[1/Prime[Range[20]]]]] (* Vincenzo Librandi, Mar 25 2017 *)
Join[{1}, 2*FoldList[Times, 1, Prime[Range[50]]]] (* G. C. Greubel, Apr 23 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Aug 03 2004
EXTENSIONS
Name amended by Antti Karttunen, Sep 24 2016
a(18)-a(19) from Vincenzo Librandi, Mar 25 2017
STATUS
approved