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A198791 Least count k that deletes the alternate (odd) numbers in the Josephus problem for a circle of numbers 1, 2, 3, ... 2*n, leaving the even numbers undeleted. 1
1, 5, 19, 27, 87, 989, 3119, 5399, 8189, 99663, 57455, 222397, 2603047, 8476649, 117917347, 290190179, 360064247, 1344262919, 3181391639, 39179386959, 204692414215, 165424388219, 2254874520599, 2922139183443, 594630799853 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Arrange 1, 2, 3, ... 2*n clockwise in a circle. Starting the count at 1, delete every k-th integer clockwise until exactly half of the numbers have been deleted. a(n) is the least positive integer k for which the deleted numbers are the odd numbers.

Deleting the alternate (even) numbers from a circle of 2*n numbers leaving the odd numbers is trivially achieved with k = 2 for all n >= 1.

LINKS

Table of n, a(n) for n=1..25.

P. Schumer, The Josephus Problem: Once More Around, Mathematics Magazine, Vol. 75:1 (2002), 12-17.

Index entries for sequences related to the Josephus Problem

CROSSREFS

Cf. A198788, A198789.

Sequence in context: A018475 A119238 A218885 * A332155 A061388 A299539

Adjacent sequences:  A198788 A198789 A198790 * A198792 A198793 A198794

KEYWORD

nonn,more

AUTHOR

William Rex Marshall, Nov 21 2011

STATUS

approved

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Last modified November 30 17:12 EST 2021. Contains 349424 sequences. (Running on oeis4.)