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A091439 Least k such that k/phi(k) >= n, where phi is Euler's totient function. 3
1, 2, 6, 210, 30030, 223092870, 13082761331670030, 3217644767340672907899084554130, 1492182350939279320058875736615841068547583863326864530410 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

These are all primorial numbers (A002110).

LINKS

Table of n, a(n) for n=1..9.

Eric Weisstein's World of Mathematics, Totient Function

MATHEMATICA

Table[prod=1; i=0; While[prod<n, i++; prod=prod/(1-1/Prime[i])]; Times@@Prime[Range[i]], {n, 1, 9}]

CROSSREFS

Sequence in context: A158096 A302344 A156517 * A285102 A285101 A176782

Adjacent sequences:  A091436 A091437 A091438 * A091440 A091441 A091442

KEYWORD

easy,nonn

AUTHOR

T. D. Noe, Jan 09 2004

STATUS

approved

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Last modified July 16 23:49 EDT 2019. Contains 325092 sequences. (Running on oeis4.)