OFFSET
1,1
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
FORMULA
MATHEMATICA
Table[Total[Select[Range[n, 2n], SquareFreeQ]], {n, 50}] (* Harvey P. Dale, Apr 29 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Jul 05 2010
STATUS
approved