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A235868 Union of 2 and powers of odd primes. 2
1, 2, 3, 5, 7, 9, 11, 13, 17, 19, 23, 25, 27, 29, 31, 37, 41, 43, 47, 49, 53, 59, 61, 67, 71, 73, 79, 81, 83, 89, 97, 101, 103, 107, 109, 113, 121, 125, 127, 131, 137, 139, 149, 151, 157, 163, 167, 169, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Numbers n such that the group G_n:={x+yi: x^2+y^2==1 (mod n); 0<=x,y<n} is cyclic; i.e., numbers n such that A060968(n) = A235863(n).

LINKS

Table of n, a(n) for n=1..59.

Jose María Grau, A. M. Oller-Marcen, Manuel Rodriguez and D. Sadornil, Fermat test with Gaussian base and Gaussian pseudoprimes, arXiv:1401.4708 [math.NT], 2014.

MATHEMATICA

Select[ Range[230], # == 2 || Mod[#, 2] == 1 && PrimeNu[#] < 2 &] (* and modified by Robert G. Wilson v, Dec 29 2016 *)

CROSSREFS

Cf. A060968, A061345, A235863.

Sequence in context: A279516 A329559 A305081 * A319151 A180934 A090332

Adjacent sequences:  A235865 A235866 A235867 * A235869 A235870 A235871

KEYWORD

nonn

AUTHOR

José María Grau Ribas, Feb 23 2014

STATUS

approved

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Last modified May 26 16:44 EDT 2020. Contains 334626 sequences. (Running on oeis4.)