※ 引述《w181496 (短毛哥)》之銘言：
: http://ppt.cc/48U~
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: 感謝!
hmm, 程式跑出來是51項（練習一下python XD）
而且遞減的情形並不平均，
前面還慢慢的，到最後卻突然快速遞減，
徒手估出正確的項數似乎不容易啊....
====================== Python 3.0 code =======================
import math
list_an = [3] #數列an的list變數
n = 0 #目前項數
an_sq = 16 #暫存變數
print('a[%d] = %f' %(n, list_an[n]))
while an_sq > 0:
list_an.append(math.sqrt(an_sq))
n+=1
print('a[%d] = %f' %(n, list_an[n]))
an_sq = list_an[n]*list_an[n-1] - 1/list_an[n-1]
print('a[%d] = sqrt(%f)!!' %(n+1, an_sq))
print('Answer: an has %d terms' %(n+1))
===============================================================
====================== console display ===================
a[0] = 3.000000
a[1] = 4.000000
a[2] = 3.415650
a[3] = 3.662322
a[4] = 3.495202
a[5] = 3.539422
a[6] = 3.476333
a[7] = 3.467229
a[8] = 3.430099
a[9] = 3.406541
a[10] = 3.375387
a[11] = 3.347364
a[12] = 3.316984
a[13] = 3.287006
a[14] = 3.255990
a[15] = 3.224629
a[16] = 3.192528
a[17] = 3.159842
a[18] = 3.126444
a[19] = 3.092345
a[20] = 3.057481
a[21] = 3.021822
a[22] = 2.985314
a[23] = 2.947908
a[24] = 2.909546
a[25] = 2.870165
a[26] = 2.829696
a[27] = 2.788061
a[28] = 2.745172
a[29] = 2.700932
a[30] = 2.655230
a[31] = 2.607941
a[32] = 2.558919
a[33] = 2.508000
a[34] = 2.454991
a[35] = 2.399665
a[36] = 2.341757
a[37] = 2.280944
a[38] = 2.216842
a[39] = 2.148971
a[40] = 2.076737
a[41] = 1.999377
a[42] = 1.915896
a[43] = 1.824950
a[44] = 1.724664
a[45] = 1.612286
a[46] = 1.483519
a[47] = 1.331021
a[48] = 1.140404
a[49] = 0.875557
a[50] = 0.348721
a[51] = sqrt(-0.836805)!!
Answer: an has 51 terms
==================================================================
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※ 編輯: oNeChanPhile 來自: 114.27.8.196 (10/21 17:06)