mathematica 这里哪里错了

len = Length[data]; list
series = Table[i, {i, 1, len}];
index = Table[Ceiling[Log[10, data[[i]] + 1]], {i, 1, len}];
For[i = 1, i <= len, i++,
(*series[[Ceiling[Log[10,data[[i]]+1]]]]+=1;*)
j = index[[i]];
series[[j]] += 1;
]
-----------------------------
我想修改table里面某些指定元素的值，可是却一直报错：

"\!\(\*
StyleBox[\"Tag\", \"MT\"]\)\!\(\*
StyleBox[\" \", \"MT\"]\)\!\(\*
StyleBox[\"\"\", \"MT\"]\)Plus in \
(635+List)[267,95,9,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,\
22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,\
45,46,47,48,49,50,<<950>>][0] is Protected.

道答案的人也不知道你在问什么……

考虑dsolve[ ] 是不是只能用在求解常微分方程。