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A276504 Numbers n such that phi(n) = phi(n+11), with Euler's totient function phi = A000010. 3
7, 11, 27, 33, 45, 63, 135, 165, 285, 304, 345, 765, 855, 964, 1144, 1575, 1744, 2134, 2295, 2805, 6424, 6604, 10725, 23584, 24244, 27645, 28875, 31174, 31354, 35445, 40755, 44164, 46672, 57046, 57057, 61444, 64005, 78975, 82095, 90195 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..40.

Kevin Ford, Solutions of phi(n) = phi(n+k) and sigma(n) = sigma(n + k), arXiv:2002.12155 [math.NT], 2020.

MATHEMATICA

Select[Range[150000], EulerPhi[#] == EulerPhi[# + 11] &]

PROG

(MAGMA) [n: n in [1..100000] | EulerPhi(n) eq EulerPhi(n+11)];

CROSSREFS

Cf. A000010.

Cf. similar sequences listed in A276503.

Sequence in context: A134043 A102373 A002643 * A039287 A045222 A002810

Adjacent sequences:  A276501 A276502 A276503 * A276505 A276506 A276507

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Sep 08 2016

STATUS

approved

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Last modified December 1 16:44 EST 2020. Contains 338846 sequences. (Running on oeis4.)