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 A076360 a(n)=Commutator[sigma,tau](n)=d0[d1[w]]-d1[d0[w]], where d0()=number of, d1()=sum of divisors of n. 6
 0, -1, 0, -2, 1, -1, 1, -3, -2, -1, 3, -6, 1, 1, 1, -4, 3, -8, 3, -4, -1, 2, 5, -3, -2, 1, 1, -4, 5, -3, 3, -6, 3, 1, 3, -9, 1, 5, 1, -3, 5, -3, 3, 0, -4, 5, 7, -12, 0, -8, 5, -6, 5, 1, 5, 1, 3, 5, 9, -12, 1, 5, -4, -6, 5, 0, 3, 0, 5, 0, 9, -20, 1, 1, -6, 0, 5, 1, 7, -10, -3, 5, 9, -16, 5, 5, 9, 3, 9, -16, 3, 4, 1, 8, 9, -10, 3, -6, 0, -9, 5, 1, 5, 1, -1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 LINKS MATHEMATICA d0[x_] := DivisorSigma[0, x] d1[x_] := DivisorSigma[1, x] Table[d0[d1[w]]-d1[d0[w]], {w, 1, 128}] CROSSREFS Cf. A000005, A000203. Sequence in context: A183214 A086291 A016442 * A089398 A047040 A047020 Adjacent sequences:  A076357 A076358 A076359 * A076361 A076362 A076363 KEYWORD easy,sign AUTHOR Labos E. (labos(AT)ana.sote.hu), Oct 08 2002 STATUS approved

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