题目

不过是英文的
In a sequence of 10 terms,the first term is 1,the second term is X,and each term after the second is the sum of the previous two terms.For example,if X=11,the sequence would be 1,11,12,23,35,58,93,151,244,395.For some values of X,the number 463 appears in the sequence.If X is a positive number,what is the sum of all the values of X for which 463 appears in the sequence.
A)1156 B）1296 C)1248 D)1528 E)1283
我想知道答案是什么 还有是怎么得到那个答案的...

提问时间：2021-04-02

答案

各数为:
1st:1
2nd:x x可以为463
3rd:x + 1 x可以为462 (462+1 = 463)
4th:2x + 1 x可以为231 (2*231+1 = 463)
5th:3x + 2 x为分数不考虑
6th:5x + 3 x = 92 (5*92+3 = 463)
7th:8x + 5 x为分数不考虑
8th:13x + 8 x = 35 (12*35+8 = 463)
9th:21x + 13 x为分数不考虑
10th:34x + 21 x = 13 (34*13 + 21 = 463)
x的和为463 + 462 + 231 + 92 + 35 + 13 = 1296