Postage stamp problem

The postage stamp problem is a mathematical riddle that asks what is the smallest postage value which cannot be placed on an envelope, if the latter can hold only a limited number of stamps, and these may only have certain specified face values.

For example, suppose the envelope can hold only three stamps, and the available stamp values are 1 cent, 2 cents, 5 cents, and 20 cents. Then the solution is 13 cents; since any smaller value can be obtained with at most three stamps (e.g. 4 = 2 + 2, 8 = 5 + 2 + 1, etc.), but to get 13 cents one must use at least four stamps.

单词	Postage stamp problem
释义	Postage stamp problem 英语百科 Postage stamp problem The postage stamp problem is a mathematical riddle that asks what is the smallest postage value which cannot be placed on an envelope, if the latter can hold only a limited number of stamps, and these may only have certain specified face values. For example, suppose the envelope can hold only three stamps, and the available stamp values are 1 cent, 2 cents, 5 cents, and 20 cents. Then the solution is 13 cents; since any smaller value can be obtained with at most three stamps (e.g. 4 = 2 + 2, 8 = 5 + 2 + 1, etc.), but to get 13 cents one must use at least four stamps.
随便看	lack of true colour rendering lack of trust lack of trying lack of uniformity lack of uniformly optimal plan lack of value Lack of volition lack of voluntary control lack of water lack of work assigned lack or loss of sexual desire Lackovic Lack Point lackquaie lacks ham lacks in lack substance lack the party spirit lack the perspective Lack tongue depressor lack unity of invention lackwit Lacky lackys Lac la Biche