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A099738 a(n) = 2*Sum_{k=1..n} (n+1-k) (Sum_{j|k} 1/floor(n/j)). 0
2, 5, 10, 15, 24, 30, 43, 52, 66, 78, 99, 107, 132, 150, 171, 188, 221, 236, 273, 291, 322, 352, 397, 409, 453, 489, 530, 558, 615, 633, 694, 727, 778, 826, 883, 900, 973, 1027, 1088, 1118, 1199, 1229, 1314, 1362, 1419, 1485, 1578, 1598, 1688, 1745, 1826, 1884 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Sequence consists entirely of integers.

First differences give A033885.

LINKS

Table of n, a(n) for n=1..52.

MATHEMATICA

f[n_] := 2Sum[(n + 1 - k)*Plus @@ (1/Floor[n/Divisors[k]]), {k, n}]; Table[ f[n], {n, 52}] (* Robert G. Wilson v, Nov 12 2004 *)

CROSSREFS

Sequence in context: A013927 A267454 A163059 * A064513 A117582 A002134

Adjacent sequences:  A099735 A099736 A099737 * A099739 A099740 A099741

KEYWORD

nonn

AUTHOR

Leroy Quet, Nov 09 2004

EXTENSIONS

More terms from Robert G. Wilson v, Nov 12 2004

STATUS

approved

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Last modified October 16 13:32 EDT 2019. Contains 328093 sequences. (Running on oeis4.)