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A307004 Numbers n such that phi^e(n) > phi^e(m) for all m < n, where phi^e(n) = A072911(n) is the number of divisors d of n such that d and n are exponentially coprime. 1
1, 8, 32, 128, 864, 2048, 3456, 7776, 31104, 279936, 497664, 1990656, 4478976, 17915904, 62208000, 97200000, 362797056, 559872000, 874800000, 1555200000, 6220800000, 13996800000, 55987200000, 349920000000, 895795200000, 1133740800000, 1399680000000, 4534963200000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The corresponding record values of phi^e are 1, 2, 4, 6, 8, 10, 12, 16, 24, ... (see the link for more values).

REFERENCES

József Sándor, On an exponential totient function, Studia Univ. Babees-Bolyai, Math., Vol. 41 (1996), pp. 91-94.

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..57

Amiram Eldar, Table of n, a(n), A072911(a(n)) for n = 1..57

László Tóth, On certain arithmetic functions involving exponential divisors, Annales Univ. Sci. Budapest., Sect. Comp., Vol. 27 (2004), pp. 285-294.

MATHEMATICA

f[n_] := Times@@EulerPhi[FactorInteger[n][[All, 2]]]; fm=0; s={}; Do[f1=f[n]; If[f1>fm, AppendTo[s, n]; fm=f1], {n, 1, 10^6}]; s

CROSSREFS

Cf. A025487, A072911.

Sequence in context: A183915 A325839 A081654 * A264280 A264390 A253105

Adjacent sequences:  A307001 A307002 A307003 * A307005 A307006 A307007

KEYWORD

nonn

AUTHOR

Amiram Eldar, Mar 19 2019

STATUS

approved

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Last modified September 22 03:54 EDT 2020. Contains 337289 sequences. (Running on oeis4.)