

A163788


a(n) is the nth J_8prime (Josephus_8 prime).


2



2, 6, 10, 62, 321, 350, 686, 3217, 4981, 21785, 22305, 350878, 378446, 500241, 576033, 659057, 917342
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OFFSET

1,1


COMMENTS

Place the numbers 1..N (N>=2) on a circle and cyclicly mark the 8th unmarked number until all N numbers are marked. The order in which the N numbers are marked defines a permutation; N is a J_8prime if this permutation consists of a single cycle of length N.
There are 17 J_8primes in the interval 2..1000000 only. No formula is known; the J_8primes were found by exhaustive search.


REFERENCES

P. R. J. Asveld, Permuting Operations on StringsTheir Permutations and Their Primes, Twente University of Technology, 2014; http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.216.1682; http://doc.utwente.nl/67513/1/pospp.pdf.
R. L. Graham, D.E. Knuth & O. Patashnik, Concrete Mathematics (1989), AddisonWesley, Reading, MA. Sections 1.3 & 3.3.


LINKS

Table of n, a(n) for n=1..17.
P. R. J. Asveld, Permuting Operations on Strings and Their Relation to Prime Numbers, Discrete Applied Mathematics 159 (2011) 19151932.


EXAMPLE

2 is a J_8prime (trivial).


CROSSREFS

A163782 through A163787 for J_2 through J_7primes. A163789 through A163800 for J_9 through J_20primes.
Sequence in context: A222559 A095107 A115113 * A324547 A093880 A080397
Adjacent sequences: A163785 A163786 A163787 * A163789 A163790 A163791


KEYWORD

nonn,more


AUTHOR

Peter R. J. Asveld, Aug 05 2009


STATUS

approved



