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 A077085 Initial values such that if A077080(x)=phi(sigma(x)+phi(x)) is started at these numbers then the sequence does not converge. 6
 534, 556, 557, 580, 624, 702, 710, 738, 739, 740, 748, 784, 789, 822, 823, 841, 852, 853, 900, 912, 913, 916, 924, 931, 938, 960, 961, 962, 1020, 1021, 1029, 1032, 1033, 1034, 1065, 1089, 1092, 1093, 1098, 1126, 1136 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS These terms are only conjectures. LINKS MATHEMATICA f[x_] := EulerPhi[DivisorSigma[1, x]+EulerPhi[x]] Do[s=Part[NestList[f, n, 100], 100]; If[Greater[s, 10000000], Print[{n, s}]], {n, 1, 10000}] CROSSREFS Cf. A000010, A000203, A065387, A077080-A077085. Sequence in context: A067803 A098258 A160176 * A165989 A183598 A252536 Adjacent sequences: A077082 A077083 A077084 * A077086 A077087 A077088 KEYWORD nonn AUTHOR Labos Elemer, Oct 28 2002 STATUS approved

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Last modified December 6 18:39 EST 2022. Contains 358644 sequences. (Running on oeis4.)