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A056012 Numbers n such that n | Sigma(n) + d(n) + Phi(n). 0
1, 2, 4, 6, 90, 408, 5856, 2200352, 11524640, 90200997888 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..10.

MAPLE

with(numtheory); List056012:=proc(q)  local n;

for n from 1 to q do if type((sigma(n)+tau(n)+phi(n))/n, integer) then print(n); fi; od;

end:  List056012(10^10); # Paolo P. Lava, Apr 29 2013

MATHEMATICA

Do[If[Mod[DivisorSigma[1, n]+DivisorSigma[0, n]+EulerPhi[n], n]==0, Print[n]], {n, 1, 10^7}]

CROSSREFS

Sequence in context: A009257 A098757 A335709 * A259050 A066719 A345269

Adjacent sequences:  A056009 A056010 A056011 * A056013 A056014 A056015

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Jul 24 2000

EXTENSIONS

a(7) corrected and a(10) added by Donovan Johnson, Nov 12 2012

STATUS

approved

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Last modified October 23 11:14 EDT 2021. Contains 348211 sequences. (Running on oeis4.)