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A023889 Sum of prime power divisors of n (not including 1). 2
0, 2, 3, 6, 5, 5, 7, 14, 12, 7, 11, 9, 13, 9, 8, 30, 17, 14, 19, 11, 10, 13, 23, 17, 30, 15, 39, 13, 29, 10, 31, 62, 14, 19, 12, 18, 37, 21, 16, 19, 41, 12, 43, 17, 17, 25, 47, 33, 56, 32, 20, 19, 53, 41, 16, 21, 22, 31, 59, 14, 61, 33, 19, 126, 18, 16, 67, 23, 26, 14 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..70.

MATHEMATICA

Array[ Plus @@ (Select[ Divisors[ # ], (Length[ FactorInteger[ # ] ]==1)& ])&, 80 ]

CROSSREFS

Sequence in context: A218890 A137761 A100769 * A093783 A096861 A118738

Adjacent sequences:  A023886 A023887 A023888 * A023890 A023891 A023892

KEYWORD

nonn

AUTHOR

Olivier Gérard

STATUS

approved

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Last modified May 18 20:38 EDT 2013. Contains 225428 sequences.