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A104363 Euler's totient of A104350(n) - 1. 3
1, 4, 10, 58, 178, 1258, 2280, 7558, 37798, 415798, 1229760, 16144536, 113488440, 567495336, 1135133998, 19295619336, 56915913600, 1085995965600, 5499724229998, 37888326510336, 423202615117920, 9425816095466520 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,2

LINKS

Amiram Eldar, Table of n, a(n) for n = 2..74

Reinhard Zumkeller, Products of largest prime factors of numbers <= n

FORMULA

a(n) = A000010(A104357(n)).

MATHEMATICA

a[n_] := EulerPhi[-1 + Product[FactorInteger[k][[-1, 1]], {k, 1, n}]]; Array[a, 50, 2] (* Amiram Eldar, Feb 12 2020 *)

CROSSREFS

Cf. A000010, A104357, A104371.

Sequence in context: A222569 A348514 A254078 * A092190 A328036 A222675

Adjacent sequences:  A104360 A104361 A104362 * A104364 A104365 A104366

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Mar 06 2005

STATUS

approved

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Last modified July 2 01:17 EDT 2022. Contains 354984 sequences. (Running on oeis4.)