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 A083682 Sum of aliquot divisors of semiprimes. 1
 3, 6, 4, 8, 10, 9, 11, 14, 6, 16, 15, 20, 13, 22, 17, 26, 8, 21, 17, 23, 32, 34, 19, 27, 40, 19, 44, 23, 46, 33, 21, 35, 50, 25, 56, 41, 29, 62, 25, 12, 64, 45, 47, 27, 70, 51, 74, 25, 35, 76, 37, 82, 57, 31, 86, 14, 63, 92, 65, 43, 29, 100, 71, 104, 37, 47, 106, 31, 75, 110, 49 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Amiram Eldar, Table of n, a(n) for n = 1..10000 FORMULA a(n) = A001065(A001358(n)). - Amiram Eldar, Sep 23 2019 EXAMPLE a(1)=3 because sum of aliquot divisors of first semiprime i.e. 4 is 1+2=3. MATHEMATICA s[n_] := DivisorSigma[1, n] - n; s /@ Select[Range[300], PrimeOmega[#]==2 &] (* Amiram Eldar, Sep 23 2019 *) CROSSREFS Cf. A001065, A001358. Sequence in context: A154890 A248176 A100000 * A021278 A143940 A321773 Adjacent sequences:  A083679 A083680 A083681 * A083683 A083684 A083685 KEYWORD easy,nonn AUTHOR Shyam Sunder Gupta, Jun 15 2003 STATUS approved

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Last modified August 8 02:15 EDT 2020. Contains 336287 sequences. (Running on oeis4.)