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A241195 Denominator of phi(prime(n)-1)/(prime(n)-1), where phi is Euler's totient function and prime(n) is the n-th prime. 6
1, 2, 2, 3, 5, 3, 2, 3, 11, 7, 15, 3, 5, 7, 23, 13, 29, 15, 33, 35, 3, 13, 41, 11, 3, 5, 51, 53, 3, 7, 7, 65, 17, 69, 37, 15, 13, 3, 83, 43, 89, 15, 95, 3, 7, 33, 35, 37, 113, 19, 29, 119, 15, 5, 2, 131, 67, 15, 69, 35, 141, 73, 51, 31, 13, 79, 33, 7, 173, 87, 11 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The numerators are in A241194.

LINKS

T. D. Noe, Table of n, a(n) for n = 1..10000

MAPLE

with(numtheory): A241195:=n->denom(phi(ithprime(n)-1) / (ithprime(n)-1)): seq(A241195(n), n=1..100); # Wesley Ivan Hurt, Apr 06 2015

MATHEMATICA

Denominator[Table[EulerPhi[p - 1]/(p - 1), {p, Prime[Range[100]]}]]

PROG

(PARI) lista(nn) = forprime(p=2, nn, print1(denominator(eulerphi(p-1)/(p-1)), ", ")); \\ Michel Marcus, Jan 03 2015

(MAGMA) [Denominator(EulerPhi(NthPrime(n)-1)/(NthPrime(n)-1)): n in [1..80]]; // Vincenzo Librandi, Apr 06 2015

CROSSREFS

Cf. A000010 (phi), A241194 (numerators).

Sequence in context: A039638 A090926 A023503 * A039640 A053811 A049840

Adjacent sequences:  A241192 A241193 A241194 * A241196 A241197 A241198

KEYWORD

nonn,frac

AUTHOR

T. D. Noe, Apr 17 2014

STATUS

approved

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Last modified May 28 21:37 EDT 2020. Contains 334690 sequences. (Running on oeis4.)