cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-2 of 2 results.

A163786 a(n) is the n-th J_6-prime (Josephus_6 prime).

Original entry on oeis.org

2, 13, 17, 18, 34, 49, 93, 97, 106, 225, 401, 745, 2506, 3037, 3370, 4713, 5206, 8585, 13418, 32237, 46321, 75525, 97889, 106193, 238513, 250657, 401902, 490118
Offset: 1

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Author

Peter R. J. Asveld, Aug 05 2009

Keywords

Comments

Place the numbers 1..N (N>=2) on a circle and cyclicly mark the 6th unmarked number until all N numbers are marked. The order in which the N numbers are marked defines a permutation; N is a J_6-prime if this permutation consists of a single cycle of length N.
There are 28 J_6-primes in the interval 2..1000000 only. No formula is known; the J_6-primes were found by exhaustive search.

Examples

			2 is a J_6-prime (trivial).
		

References

  • R. L. Graham, D. E. Knuth & O. Patashnik, Concrete Mathematics (1989), Addison-Wesley, Reading, MA. Sections 1.3 & 3.3.

Crossrefs

Cf. A163782 through A163785 for J_2- through J_5-primes.
Cf. A163787 through A163800 for J_7- through J_20-primes.

A163788 a(n) is the n-th J_8-prime (Josephus_8 prime).

Original entry on oeis.org

2, 6, 10, 62, 321, 350, 686, 3217, 4981, 21785, 22305, 350878, 378446, 500241, 576033, 659057, 917342
Offset: 1

Views

Author

Peter R. J. Asveld, Aug 05 2009

Keywords

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_8-prime if this permutation consists of a single cycle of length N.
There are 17 J_8-primes in the interval 2..1000000 only. No formula is known; the J_8-primes were found by exhaustive search.

Examples

			2 is a J_8-prime (trivial).
		

References

  • R. L. Graham, D. E. Knuth & O. Patashnik, Concrete Mathematics (1989), Addison-Wesley, Reading, MA. Sections 1.3 & 3.3.

Crossrefs

Cf. A163782 through A163787 for J_2- through J_7-primes.
Cf. A163789 through A163800 for J_9- through J_20-primes.
Showing 1-2 of 2 results.