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A227535 Exponents e such that n^e is the least totient for some even n and all even k < n have a totient of the form k^f for some f < e. 2
2, 3, 4, 5, 15, 17, 23, 42, 44, 47, 68, 80, 107, 130, 142, 162, 184 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Records in A227533.

LINKS

Table of n, a(n) for n=1..17.

FORMULA

a(n) = A227533(A227534(n)/2).

PROG

(PARI) r=0; forstep(n=2, 1e5, 2, t=1; while(!istotient(n^t++), ); if(t>r, r=t; print1(t", ")))

\\ See also A227533 for a more efficient method of computing terms.

CROSSREFS

Cf. A227533, A227534.

Sequence in context: A199165 A202423 A171593 * A096774 A201356 A183528

Adjacent sequences:  A227532 A227533 A227534 * A227536 A227537 A227538

KEYWORD

nonn,hard

AUTHOR

Charles R Greathouse IV, Jul 14 2013

EXTENSIONS

a(14) from Charles R Greathouse IV, Jul 16 2013

a(15) from Charles R Greathouse IV, Jul 17 2013

a(16)-a(17) from Charles R Greathouse IV, Jul 19 2013

STATUS

approved

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Last modified January 17 17:07 EST 2019. Contains 319235 sequences. (Running on oeis4.)