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A052155 Pseudoprimes to both base 2 and base 3, i.e., intersection of A001567 and A005935. 8
1105, 1729, 2465, 2701, 2821, 6601, 8911, 10585, 15841, 18721, 29341, 31621, 41041, 46657, 49141, 52633, 63973, 75361, 83333, 83665, 88561, 90751, 93961, 101101, 104653, 107185, 115921, 126217, 162401, 172081, 176149, 188461 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000 (first 201 terms from R. J. Mathar)

J. Bernheiden, Pseudoprimes (Text in German)

Index entries for sequences related to pseudoprimes

MATHEMATICA

Select[ Range[228240], !PrimeQ[ # ] && PowerMod[2, # - 1, # ] == 1 && PowerMod[3, # - 1, # ] == 1 &]

PROG

(PARI) is(n)=!isprime(n)&&Mod(2, n)^(n-1)==1&&Mod(3, n)^(n-1)==1 \\ Charles R Greathouse IV, Apr 12 2012

CROSSREFS

Cf. A001567, A005935, A083737.

Sequence in context: A025314 A025287 A025305 * A097102 A281877 A159781

Adjacent sequences:  A052152 A052153 A052154 * A052156 A052157 A052158

KEYWORD

nice,nonn

AUTHOR

Harvey P. Dale, Jan 24 2000

STATUS

approved

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Last modified December 10 04:37 EST 2018. Contains 318044 sequences. (Running on oeis4.)