login
This site is supported by donations to The OEIS Foundation.

 

Logo

Invitation: celebrating 50 years of OEIS, 250000 sequences, and Sloane's 75th, there will be a conference at DIMACS, Rutgers, Oct 9-10 2014.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A141350 Overpseudoprimes of base 3. 4
121, 703, 3281, 8401, 12403, 31621, 44287, 47197, 55969, 74593, 79003, 88573, 97567, 105163, 112141, 211411, 221761, 226801, 228073, 293401, 313447, 320167, 328021, 340033, 359341, 432821, 443713, 453259, 478297, 497503, 504913, 679057, 709873, 801139, 867043, 894781, 973241, 1042417 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

If h_3(n) is the multiplicative order of 3 modulo n, r_3(n) is the number of cyclotomic cosets of 3 modulo n then, by the definition, n is an overpseudoprime of base 3 if h_3(n)*r_3(n)+1=n. These numbers are in A020229.

In particular, if n is squarefree such that its prime factorization is n=p_1*...*p_k, then n is overpseudoprime of base 3 iff h_3(p_1)=...=h_3(p_k).

REFERENCES

Vladimir Shevelev, Gilberto Garcia-Pulgarin, Juan Miguel Velasquez-Soto and John H. Castillo, Overpseudoprimes, and Mersenne and Fermat numbers as primover numbers, Arxiv preprint arXiv:1206:0606, 2012. - From N. J. A. Sloane, Oct 28 2012

LINKS

Table of n, a(n) for n=1..38.

V. Shevelev, Overpseudoprimes, Mersenne Numbers and Wieferich Primes, arXiv:0806.3412v8 [math.NT]

CROSSREFS

Cf. A141232, A137576, A001262, A020229, A062117, A006694.

Sequence in context: A014749 A048950 A020229 * A235408 A190877 A238250

Adjacent sequences:  A141347 A141348 A141349 * A141351 A141352 A141353

KEYWORD

nonn

AUTHOR

Vladimir Shevelev, Jun 27 2008, corrected Sep 07 2008

EXTENSIONS

a(10)-a(38) from Gilberto Garcia-Pulgarin - Vladimir Shevelev, Feb 06 2012

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified September 21 22:14 EDT 2014. Contains 247025 sequences.