OFFSET
0,5
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 0..10000
FORMULA
a(n)=sum{k=0..n, floor(sqrt(n)/(k+1))}.
PROG
(Haskell)
a113215 n = a113215_list !! n
a113215_list = concat $ zipWith take
[1, 3 ..] $ map (repeat . a006218) [0 ..]
-- Reinhard Zumkeller, May 30 2015
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Oct 18 2005
STATUS
approved