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 A117004 a(n) = sigma(n) - A079667(n). 8
 1, 2, 2, 4, 2, 6, 2, 6, 5, 6, 2, 12, 2, 6, 8, 10, 2, 12, 2, 14, 8, 6, 2, 20, 7, 6, 8, 14, 2, 22, 2, 14, 8, 6, 12, 26, 2, 6, 8, 24, 2, 24, 2, 14, 18, 6, 2, 32, 9, 16, 8, 14, 2, 24, 12, 28, 8, 6, 2, 42, 2, 6, 22, 22, 12, 24, 2, 14, 8, 30, 2, 48, 2, 6, 18, 14, 16, 24, 2, 40, 17, 6, 2, 46, 12, 6, 8, 30 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 REFERENCES H. J. S. Smith, Report on the Theory of Numbers, reprinted in Vol. 1 of his Collected Math. Papers, Chelsea, NY, 1979, see p. 322. LINKS Seiichi Manyama, Table of n, a(n) for n = 1..10000 FORMULA G.f.: sum(n>=1, n*x^(n^2)*(1+x^n)/(1-x^n) ). [Joerg Arndt, Jan 30 2011] a(n) = Sum_{d|n} min(d, n/d). - Seiichi Manyama, Dec 27 2017 PROG (PARI) {a(n) = sumdiv(n, d, min(d, n/d))} \\ Seiichi Manyama, Dec 27 2017 CROSSREFS Cf. A000203, A079667. Sequence in context: A270492 A002322 A127835 * A128982 A096216 A121599 Adjacent sequences:  A117001 A117002 A117003 * A117005 A117006 A117007 KEYWORD nonn AUTHOR N. J. A. Sloane, Apr 15 2006 STATUS approved

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Last modified March 24 06:19 EDT 2018. Contains 301179 sequences. (Running on oeis4.)