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A009278 a(n) = lcm(d(n), sigma(n)). 5
1, 6, 4, 21, 6, 12, 8, 60, 39, 36, 12, 84, 14, 24, 24, 155, 18, 78, 20, 42, 32, 36, 24, 120, 93, 84, 40, 168, 30, 72, 32, 126, 48, 108, 48, 819, 38, 60, 56, 360, 42, 96, 44, 84, 78, 72, 48, 620, 57, 186, 72, 294, 54, 120, 72, 120, 80, 180, 60, 168, 62, 96, 312, 889, 84, 144, 68 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..10000

MATHEMATICA

Table[LCM[Length[Divisors[n]], DivisorSigma[1, n]], {n, 1, 100}] (* Stefan Steinerberger, Apr 13 2006 *)

PROG

(PARI) A009278(n) = lcm(numdiv(n), sigma(n)); \\ Antti Karttunen, Sep 10 2017

CROSSREFS

Cf. A000005, A000203, A009205, A009286.

Sequence in context: A317858 A212891 A107983 * A213573 A321417 A185734

Adjacent sequences:  A009275 A009276 A009277 * A009279 A009280 A009281

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified June 20 10:03 EDT 2021. Contains 345162 sequences. (Running on oeis4.)