？
by ez_lcw @ 2020-05-30 13:28:47
$f(x)=f(x-1)+1$
`$f(x)=f(x-1)+1$`
是这个吗？
by impuk @ 2020-05-30 13:29:00
$f_i=f_{i-1}+1$？
by ez_lcw @ 2020-05-30 13:29:19
应该不是、、、、、
by bovine__kebi @ 2020-05-30 13:29:25
$$a_n = \sum_{i=1}^k f_ia_{n-i}$$
by NaCly_Fish @ 2020-05-30 13:29:34
$f_i=f_{i-1}+1$
`$f_i=f_{i-1}+1$`
by bovine__kebi @ 2020-05-30 13:29:53
@[NaCly_Fish](/user/115864) 鱼鱼/qq
by bovine__kebi @ 2020-05-30 13:30:05
$$f_i=f_{i-1}+f_{i-2}$$
by liqingyang @ 2020-05-30 13:30:12
草我写错了
by Lates @ 2020-05-30 13:30:39
是递等式
by Lates @ 2020-05-30 13:30:47