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A392305
Compensation points to be given to the presenter such that the game "Fill your basket" with n coins is fair.
0
1, 1, 1, 2, 3, 3, 3, 3, 3, 4, 4, 5, 5, 5, 6, 6
OFFSET
1,4
COMMENTS
"Fill your basket" is a two-players game. The "presenter" selects one of three baskets and the "placer" puts one of n coins with values from 1 to n in that basket. This is repeated n times. At the end the placer is awarded the largest sum of the three baskets and the presenter is awarded the second largest sum. Since the placer has an advantage a compensation, to be agreed upon before the game, is paid to the presenter. The goal of both players is to achieve more points than the opponent. a(n) is the compensation which needs to be paid such that the game will end in a draw if both players apply the optimal strategy.
EXAMPLE
a(3)=1. The placer must not put coin 3 in the first basket, because the presenter would present in the next two turns the second basket and would achieve a 3:3. If the placer puts 1 in the first basket, they either win 4:2 if the first basket is presented again or 3:2 if a different basket is presented where coin 2 must be placed. If the placer puts 2 in the first basket, they either win 5:1 if the first basket is presented again or 3:2 if a different basket is presented where coin 1 must be placed. Hence when keeping coin 3 to the very end, the presenter can always force a result of 3:2 and therefore a(3)=1 coin must be given as compensation to the presenter.
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Ruediger Jehn, Jan 06 2026
STATUS
approved