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A043343 Numbers n such that there is no k > n such that phi(k) = phi(n), where phi is Euler's totient function. 4
2, 6, 12, 18, 22, 30, 42, 46, 54, 58, 60, 62, 66, 90, 94, 98, 106, 118, 120, 126, 134, 138, 142, 150, 158, 162, 166, 174, 198, 206, 210, 214, 240, 242, 250, 254, 262, 270, 274, 276, 278, 282, 294, 298, 302, 318, 330, 334, 346, 348, 354, 358, 378, 382, 394, 398 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Paul Tek, Table of n, a(n) for n = 1..980

FORMULA

A066659(a(n)) = 0.

A028476(a(n)) = a(n).

MATHEMATICA

Flatten@ Position[#, 0] &@ Table[k = n + 1; While[And[k <= 2 n + 1, EulerPhi@ k != EulerPhi@ n], k++]; Boole[k < 2 n + 1] k, {n, 400}] (* Michael De Vlieger, Dec 31 2016 *)

CROSSREFS

Cf. A066659.

Sequence in context: A263269 A262503 A263082 * A066080 A319270 A071707

Adjacent sequences:  A043340 A043341 A043342 * A043344 A043345 A043346

KEYWORD

nonn

AUTHOR

Vladeta Jovovic, Jan 12 2002

EXTENSIONS

Offset corrected by Paul Tek, Sep 25 2015

Definition clarified by Alonso del Arte, Dec 31 2016

STATUS

approved

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Last modified March 26 10:57 EDT 2019. Contains 321491 sequences. (Running on oeis4.)