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A009230 a(n) = lcm(n, d(n)). 6
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

T. D. Noe and 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

Cf. A000005, A033950.

Sequence in context: A245785 A145102 A145103 * A069491 A127698 A130503

Adjacent sequences:  A009227 A009228 A009229 * A009231 A009232 A009233

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified May 21 19:18 EDT 2019. Contains 323444 sequences. (Running on oeis4.)