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A066687 Numbers n such that prime(n) == n (mod phi(n)). 0
1, 2, 3, 11, 15, 67, 209, 439, 1285, 4393, 11513, 31037, 133361, 181411, 225209, 637337, 637339, 7351279, 10253001, 10553551, 339144639, 416538907, 639770919, 4631809783 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(25) > 10^12. - Donovan Johnson, Mar 14 2010

LINKS

Table of n, a(n) for n=1..24.

EXAMPLE

p(3) = 5 is congruent to 3 mod phi(2) = 2, so 3 is a term of the sequence.

MATHEMATICA

Select[ Range[ 1, 10^6 ], Mod[ #, EulerPhi[ # ] ] == Mod[ Prime[ # ], EulerPhi[ # ] ] & ]

CROSSREFS

Sequence in context: A293026 A178430 A295128 * A144979 A194558 A076514

Adjacent sequences:  A066684 A066685 A066686 * A066688 A066689 A066690

KEYWORD

nonn

AUTHOR

Joseph L. Pe, Jan 11 2002

EXTENSIONS

a(18)-a(24) from Donovan Johnson, Mar 14 2010

STATUS

approved

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Last modified September 16 07:19 EDT 2021. Contains 347469 sequences. (Running on oeis4.)