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A123239 "Mangammal primes": prime numbers which are impossible factors of 3^n-2, i.e. they do not divide 3^n-2 for any value of n. 11
2, 3, 11, 13, 37, 41, 59, 61, 67, 73, 83, 103, 107, 109, 131, 151, 157, 179, 181, 193, 227, 229, 251, 271, 277, 307, 313, 347, 349, 367, 373, 397, 419, 421, 433, 443, 467, 491, 523, 541, 547, 563, 577, 587, 613, 619, 659, 661, 673, 683, 709, 733, 757, 761 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

That the sequence is infinite can be proved using a theorem in "Euler's Generalisation Of Fermat's Theorem - A Further Generalisation".

REFERENCES

A. K. Devaraj, "Euler's Generalization of Fermat's Theorem-A Further Generalization", in ISSN #1550-3747, Proceedings of Hawaii Intl Conference on Statistics, Mathematics & Related Fields, 2004.

MATHEMATICA

Select[Prime[Range[135]], !MemberQ[Table[PowerMod[3, k, # ], {k, #-1}], 2]&] - Farideh Firoozbakht (mymontain(AT)yahoo.com), Oct 11 2006

CROSSREFS

Sequence in context: A157884 A085306 A161322 * A048891 A191057 A068820

Adjacent sequences:  A123236 A123237 A123238 * A123240 A123241 A123242

KEYWORD

nonn

AUTHOR

A. K. Devaraj (dkandadai(AT)gmail.com), Oct 07 2006

EXTENSIONS

More terms from Don Reble (djr(AT)nk.ca), Oct 07 2006

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Last modified February 17 12:38 EST 2012. Contains 206021 sequences.