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A113215
Repeat A006218(n) 2n+1 times.
1
0, 1, 1, 1, 3, 3, 3, 3, 3, 5, 5, 5, 5, 5, 5, 5, 8, 8, 8, 8, 8, 8, 8, 8, 8, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20
OFFSET
0,5
LINKS
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
Cf. A006218.
Sequence in context: A112593 A213809 A204854 * A105591 A130497 A178154
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Oct 18 2005
STATUS
approved