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A003968 Möbius transform of A003959. 3
1, 2, 3, 6, 5, 6, 7, 18, 12, 10, 11, 18, 13, 14, 15, 54, 17, 24, 19, 30, 21, 22, 23, 54, 30, 26, 48, 42, 29, 30, 31, 162, 33, 34, 35, 72, 37, 38, 39, 90, 41, 42, 43, 66, 60, 46, 47, 162, 56, 60, 51, 78, 53, 96, 55, 126, 57, 58, 59, 90, 61, 62, 84, 486, 65, 66, 67, 102, 69 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(n) = n for squarefree n; otherwise, a(n) > n. - Ivan Neretin, May 13 2015

Dirichlet inverse of A062953. - Werner Schulte, Oct 25 2018

LINKS

Ivan Neretin, Table of n, a(n) for n = 1..10000

FORMULA

Multiplicative with a(p^e) = p(p+1)^(e-1). - David W. Wilson, Sep 01 2001

MATHEMATICA

Table[{pp, aa} = Transpose[FactorInteger[n]]; Times @@ (pp*(pp + 1)^(aa - 1)), {n, 70}]  (* Ivan Neretin, May 13 2015 *)

PROG

(PARI) a(n) = {my(f=factor(n)); for (i=1, #f~, p= f[i, 1]; f[i, 1] = p*(p+1)^(f[i, 2]-1); f[i, 2] = 1); factorback(f); } \\ Michel Marcus, Feb 26 2015

CROSSREFS

Cf. A062953.

Sequence in context: A057723 A335835 A142151 * A076734 A242314 A242311

Adjacent sequences:  A003965 A003966 A003967 * A003969 A003970 A003971

KEYWORD

nonn,mult

AUTHOR

Marc LeBrun

EXTENSIONS

More terms from David W. Wilson, Aug 29 2001

STATUS

approved

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Last modified September 29 04:22 EDT 2020. Contains 337420 sequences. (Running on oeis4.)