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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 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 December 14 01:41 EST 2019. Contains 329978 sequences. (Running on oeis4.)