magic number

基本解释

Q. Is there a magic number of points for a business plan?
对于商业计划的要点来说是否存在一个“魔力数字”？
There's no magic number and no basic guideline for what number to pick; this is a decision you need to make.
并没有所谓“神奇”的数字，也没有用于选择哪个数字的基本原则，这需要您自己做出决定。
Even if governments where able to control the current account balance—which they are not given reasonably open goods and capital markets—there is no single magic number they should aim for.
即使与会的各国政府能够控制经常帐户余额（假定各国没有合理开放商品和资本市场），也没有一个它们该绳之以准的神奇数字。

Nobody is going to go over the magic number needed to nominate on the Democratic side.
NPR: Day of Reckoning Ahead for Clinton, Obama
And it's looking increasingly like it won't be possible to reach that magic number.
FORBES: Magazine Article
As noted earlier, there is no magic number that is right for everyone.
FORBES: What Portfolio Withdrawal Rate Can You Live With?

any of the numbers 2, 8, 20, 28, 50, 82, and 126. Nuclides with these numbers of nucleons appear to have greater stability than other nuclides 2820285082126

幻数
According to the secondary differences of energy,n=3,6,9,12,15,18 is 'magic number'of(MgO))_n clusters.
团簇能量的二阶差分表明,3、6、9、12、15、18为团簇的为幻数。
化学
幻数