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A137148 a(n) = n*phi(n) for nonprime n. 0
1, 8, 12, 32, 54, 40, 48, 84, 120, 128, 108, 160, 252, 220, 192, 500, 312, 486, 336, 240, 512, 660, 544, 840, 432, 684, 936, 640, 504, 880, 1080, 1012, 768, 2058, 1000, 1632, 1248, 972, 2200, 1344, 2052, 1624, 960, 1860, 2268, 2048, 3120, 1320, 2176, 3036 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Numbers which occur in A002618 but not A036689
LINKS
FORMULA
a(n) = A002618(A018252(n)). - R. J. Mathar, Jan 18 2021
MATHEMATICA
a = {}; Do[If[PrimeQ[n], [null], AppendTo[a, n EulerPhi[n]]], {n, 1, 100}]; a
CROSSREFS
Sequence in context: A083485 A217156 A066934 * A211778 A045018 A067681
KEYWORD
nonn
AUTHOR
Artur Jasinski, Jan 23 2008
STATUS
approved

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Last modified March 28 09:04 EDT 2024. Contains 371240 sequences. (Running on oeis4.)