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A088738 Sum of semiprime divisors of n-th composite number. 2
4, 6, 4, 9, 10, 10, 14, 15, 4, 15, 14, 21, 22, 10, 25, 26, 9, 18, 31, 4, 33, 34, 35, 19, 38, 39, 14, 41, 26, 24, 46, 10, 49, 35, 51, 30, 15, 55, 18, 57, 58, 35, 62, 30, 4, 65, 61, 38, 69, 59, 19, 74, 40, 42, 77, 71, 14, 9, 82, 45, 85, 86, 87, 26, 40, 91, 50, 93, 94, 95, 10 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..5000

MATHEMATICA

spd[n_]:=Total[Select[Divisors[n], PrimeOmega[#]==2&]]; spd/@Select[ Range[ 100], CompositeQ] (* Harvey P. Dale, Nov 25 2014 *)

CROSSREFS

Cf. A088737, A002808, A001358.

Sequence in context: A113209 A088739 A088740 * A114595 A256415 A143545

Adjacent sequences:  A088735 A088736 A088737 * A088739 A088740 A088741

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Oct 12 2003

STATUS

approved

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Last modified February 27 06:36 EST 2020. Contains 332299 sequences. (Running on oeis4.)