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A052155 Pseudoprimes to both base 2 and base 3, i.e., intersection of A001567 and A005935. 13
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)
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
Sequence in context: A025314 A025287 A025305 * A097102 A281877 A159781
KEYWORD
nice,nonn
AUTHOR
Harvey P. Dale, Jan 24 2000
STATUS
approved

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Last modified April 24 14:54 EDT 2024. Contains 371960 sequences. (Running on oeis4.)