A318241 Column 3 of array in A318240.

0, 1, 1, 3, 3, 4, 4, 4, 4, 6, 6, 6, 7, 7, 7, 9, 9, 9, 10, 10, 10, 12, 12, 12, 13, 13, 13

Offset

1,4

Comments

The next value a(28) is either 15 or 16.

a(6k+1) = a(6k+2) = a(6k+3) = 3k+1 for k >= 1. This follows from the solution to Kirkman's schoolgirl problem with n schoolgirls.

The values of a(6k), a(6k-1) and a(6k-2) are either 3k or 3k+1.

Links

Table of n, a(n) for n=1..27.

D. K. Ray-Chaudhuri and Richard M. Wilson, Solution of Kirkman's schoolgirl problem, in Proceedings of Symposia in Pure Mathematics, Volume 19, 1971.

Wikipedia, Kirkman's schoolgirl problem

Crossrefs

Cf. A318240.

Sequence in context: A090589 A163400 A090972 * A181742 A179843 A319198

Adjacent sequences: A318238 A318239 A318240 * A318242 A318243 A318244

Keyword

nonn,more

Author

Floris P. van Doorn, Aug 25 2018

Status

approved