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A067933 Primes p such that p == -1 (mod phi(p-1)). 2
2, 3, 5, 7, 11, 31, 71, 2591, 131071 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

No more terms up to 373587883 (the 20 millionth prime).

LINKS

Table of n, a(n) for n=1..9.

MATHEMATICA

Do[p = Prime[n]; If[ Mod[p + 1, EulerPhi[p - 1]] == 0, Print[p]], {n, 1, 10^8}] (* Cloitre *)

Select[Prime[Range[10^5]], Mod[#, EulerPhi[# - 1]] == EulerPhi[# - 1] - 1 &] (* Alonso del Arte, Sep 26 2011 *)

CROSSREFS

Sequence in context: A085300 A119388 A093487 * A005234 A254225 A334026

Adjacent sequences:  A067930 A067931 A067932 * A067934 A067935 A067936

KEYWORD

more,nonn

AUTHOR

Benoit Cloitre, Feb 22 2002

EXTENSIONS

Edited by Robert G. Wilson v, Feb 27 2002

STATUS

approved

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Last modified September 18 07:17 EDT 2021. Contains 347510 sequences. (Running on oeis4.)