A119486 Numbers of children for which there is a subset which cannot be generated by a counting-out game.

9, 12, 15, 18, 20, 21, 24, 25, 27, 28, 30, 33

Offset

1,1

Comments

The numbers were generated by an exhaustive search via a C-program.

Links

Table of n, a(n) for n=1..12.

Formula

Conjecture (by J. Fricke and G. Woeginger): The sequence contains all numbers n with an odd prime divisor p satisfying n/p>2.

Example

For 9 children 1,2,3,4,5,6,7,8,9, there is no possibility to select 3,4,6,7 (in any order) by a counting-out game, e.g. for selecting 3,4,6,7 the count-to number has to be 3 mod 9, 1 mod 8, 2 mod 7 and 1 mod 6, which is impossible.

Crossrefs

Complement of A119485.

Sequence in context: A345498 A248903 A138945 * A235341 A356333 A342082

Adjacent sequences: A119483 A119484 A119485 * A119487 A119488 A119489

Keyword

nonn,more

Author

Jan Fricke, May 23 2006

Status

approved