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A105221 a(n) = the sum of n's distinct prime factors below n. 8
0, 0, 0, 2, 0, 5, 0, 2, 3, 7, 0, 5, 0, 9, 8, 2, 0, 5, 0, 7, 10, 13, 0, 5, 5, 15, 3, 9, 0, 10, 0, 2, 14, 19, 12, 5, 0, 21, 16, 7, 0, 12, 0, 13, 8, 25, 0, 5, 7, 7, 20, 15, 0, 5, 16, 9, 22, 31, 0, 10, 0, 33, 10, 2, 18, 16, 0, 19, 26, 14, 0, 5, 0, 39, 8, 21, 18, 18, 0, 7, 3, 43, 0, 12, 22, 45 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

a(n) = A008472(n) - A010051(n) * n. - Reinhard Zumkeller, Apr 05 2013

LINKS

T. D. Noe, Table of n, a(n) for n=1..1000

EXAMPLE

a(12)=5 because 12's distinct prime factors 2 and 3 sum to 5.

PROG

(Haskell)

a105221 n = a008472 n - n * fromIntegral (a010051 n)

-- Reinhard Zumkeller, Apr 05 2013

CROSSREFS

Cf. A003508.

Cf. A008472

Sequence in context: A171388 A086134 A071090 * A215339 A061376 A058974

Adjacent sequences:  A105218 A105219 A105220 * A105222 A105223 A105224

KEYWORD

easy,nonn

AUTHOR

Alexandre Wajnberg, Apr 13 2005

EXTENSIONS

Edited by Don Reble, Nov 17 2005

STATUS

approved

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Last modified April 23 06:08 EDT 2019. Contains 322381 sequences. (Running on oeis4.)