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A048950 Base 3 Euler-Jacobi pseudoprimes. 3
121, 703, 1729, 1891, 2821, 3281, 7381, 8401, 8911, 10585, 12403, 15457, 15841, 16531, 18721, 19345, 23521, 24661, 28009, 29341, 31621, 41041, 44287, 46657, 47197, 49141, 50881, 52633, 55969, 63139, 63973, 74593, 75361, 79003, 82513 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Odd composite n with gcd(n,3)=1 and 3^((n-1)/2) == (3,n) (mod n) where (.,.) is the Jacobi symbol. - R. J. Mathar, Jul 15 2012

The base 5 Euler-Jacobi pseudoprimes are 781, 1541, 1729, 5461, 5611, 6601, 7499,... - R. J. Mathar, Jul 15 2012

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

A. Rotkiewicz, On Euler Lehmer pseudoprimes and strong Lehmer pseudoprimes with Parameters L, Q in arithmetic progressions, Math. Comp 39 (159) (1982) 239-247.

Eric Weisstein's World of Mathematics, Euler-Jacobi Pseudoprime.

Index entries for sequences related to pseudoprimes

MATHEMATICA

Select[Range[1, 10^5, 2], GCD[#, 3] == 1 && CompositeQ[#] && PowerMod[3, (# - 1)/2, #] == Mod[JacobiSymbol[3, #], #] &] (* Amiram Eldar, Jun 28 2019 *)

PROG

(PARI) is(n) = n%2==1 && gcd(n, 3)==1 && Mod(3, n)^((n-1)/2)==kronecker(3, n)

forcomposite(c=1, 83000, if(is(c), print1(c, ", "))) \\ Felix Fröhlich, Jul 15 2019

CROSSREFS

Cf. A047713 (base 2), A005935.

Sequence in context: A036306 A014749 A262051 * A020229 A141350 A235408

Adjacent sequences:  A048947 A048948 A048949 * A048951 A048952 A048953

KEYWORD

nonn

AUTHOR

Eric W. Weisstein

STATUS

approved

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Last modified August 25 05:19 EDT 2019. Contains 326318 sequences. (Running on oeis4.)