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A070033 Least number m such that integer part of sigma(m)/phi(m) equals n. 2
1, 3, 2, 10, 20, 6, 12, 42, 30, 60, 120, 210, 630, 420, 840, 2520, 10080, 9240, 27720, 55440, 120120, 360360, 720720, 2162160, 6126120, 12252240, 36756720, 116396280, 232792560, 698377680, 2677114440, 5354228880, 26771144400, 155272637520, 465817912560 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(36) <= 1552726375200. a(37) <= 9316358251200. - Donovan Johnson, Oct 18 2012

LINKS

Table of n, a(n) for n=1..35.

FORMULA

a(n)=Min{x : Floor[A000203(x)/A000010(x)]=n}

MATHEMATICA

t=Table[0, {100}]; Do[c=Floor[DivisorSigma[1, n]/EulerPhi[n]]; If[c<101&&t[[c]]== 0, t[[c]]=n], {n, 1, 100000}]; t

CROSSREFS

Cf. A000203, A000010, A070032.

Sequence in context: A192617 A082219 A034461 * A107334 A335719 A096073

Adjacent sequences:  A070030 A070031 A070032 * A070034 A070035 A070036

KEYWORD

nonn

AUTHOR

Labos Elemer, Apr 15 2002

EXTENSIONS

Two more terms from Labos Elemer, May 18 2004

a(30)-a(33) from Donovan Johnson, Apr 14 2010

a(34)-a(35) from Donovan Johnson, Oct 18 2012

STATUS

approved

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Last modified August 7 19:57 EDT 2020. Contains 336279 sequences. (Running on oeis4.)