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A163791
a(n) is the n-th J_11-prime (Josephus_11 prime).
2
3, 9, 27, 47, 63, 185, 617, 15189, 56411, 182439, 271607, 658521
OFFSET
1,1
COMMENTS
Place the numbers 1..N (N>=2) on a circle and cyclicly mark the 11th unmarked number until all N numbers are marked. The order in which the N numbers are marked defines a permutation; N is a J_11-prime if this permutation consists of a single cycle of length N.
There are 12 J_11-primes in the interval 2..1000000 only. No formula is known; the J_11-primes have been found by exhaustive search.
REFERENCES
R. L. Graham, D. E. Knuth & O. Patashnik, Concrete Mathematics (1989), Addison-Wesley, Reading, MA. Sections 1.3 & 3.3.
EXAMPLE
All J_11-primes are odd.
CROSSREFS
Cf. A163782 through A163790 for J_2- through J_10-primes.
Cf. A163792 through A163800 for J_12- through J_20-primes.
Sequence in context: A056024 A116475 A337948 * A248078 A057829 A181047
KEYWORD
nonn,more,changed
AUTHOR
Peter R. J. Asveld, Aug 04 2009
STATUS
approved