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Sequence 6, 24, 60120, (how to fill in brackets?
two hundred and ten
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Analysis——
6+（6*3）=24
24+（6*6）=60
60+（6*10）=120
therefore
120+（6*15）=210
Known sequence: 1 / 6.1/24.1/60.1/120?
First of all, find out the law that he leads to. After 1 / N (n + 1) / 2 * (2n + 4) is simplified, 1 / N (n + 1) (n + 2) column term is obtained
1/2(1/n(n+1) - 1/(n+1)(n+2) )
When n is 10, s = 65 / 264
Sequence: 1,2,6,24?
You can't bring an-1 with you
n!
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