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A119486 Numbers of children for which there is a subset which cannot be generated by a counting-out game. 1
9, 12, 15, 18, 20, 21, 24, 25, 27, 28, 30, 33 (list; graph; refs; listen; history; text; internal format)
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: A176656 A248903 A138945 * A235341 A161345 A102655

Adjacent sequences:  A119483 A119484 A119485 * A119487 A119488 A119489

KEYWORD

more,nonn

AUTHOR

Jan Fricke (fricke(AT)math.uni-siegen.de), May 23 2006, Jun 06 2006

STATUS

approved

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Last modified July 6 08:51 EDT 2020. Contains 335476 sequences. (Running on oeis4.)