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A009230 a(n) = lcm(n, d(n)). 9
1, 2, 6, 12, 10, 12, 14, 8, 9, 20, 22, 12, 26, 28, 60, 80, 34, 18, 38, 60, 84, 44, 46, 24, 75, 52, 108, 84, 58, 120, 62, 96, 132, 68, 140, 36, 74, 76, 156, 40, 82, 168, 86, 132, 90, 92, 94, 240, 147, 150, 204, 156, 106, 216, 220, 56, 228, 116, 118, 60, 122, 124, 126, 448 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Fixed points of this sequence are the refactorable numbers (A033950), i.e. a(A033950(n)) = A033950(n). - Labos Elemer, Nov 18 2002
LINKS
Alois P. Heinz, Table of n, a(n) for n = 1..20000 (first 1000 terms from T. D. Noe)
MAPLE
a:= n-> ilcm(n, numtheory[tau](n)):
seq(a(n), n=1..100); # Alois P. Heinz, Jan 14 2017
MATHEMATICA
Table[LCM[n, DivisorSigma[0, n]], {n, 70}] (* Harvey P. Dale, Jul 31 2016 *)
CROSSREFS
Sequence in context: A145102 A145103 A329654 * A354421 A069491 A127698
KEYWORD
nonn
AUTHOR
STATUS
approved

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Last modified March 18 22:56 EDT 2024. Contains 370952 sequences. (Running on oeis4.)