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A088738 Sum of semiprime divisors of n-th composite number. 2

%I

%S 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,

%T 39,14,41,26,24,46,10,49,35,51,30,15,55,18,57,58,35,62,30,4,65,61,38,

%U 69,59,19,74,40,42,77,71,14,9,82,45,85,86,87,26,40,91,50,93,94,95,10

%N Sum of semiprime divisors of n-th composite number.

%H G. C. Greubel, <a href="/A088738/b088738.txt">Table of n, a(n) for n = 1..5000</a>

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

%Y Cf. A088737, A002808, A001358.

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, Oct 12 2003

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Last modified April 6 16:14 EDT 2020. Contains 333276 sequences. (Running on oeis4.)