一个有趣的数列题

This topic created in 3171 days ago, the information mentioned may be changed or developed.

122333444455555666666 an=[((√8n － 7)－ 1)/2]－ 1 如何证明？

2 replies • 2017-11-10 12:28:21 +08:00

adcen

Nov 10, 2017 via Android

问题是如何推出通项

xml123

Nov 10, 2017

an=round(sqrt(2*n))
根据增长率拟合一下系数就行了