Problem 1
If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23.
Find the sum of all the multiples of 3 or 5 below 1000.
如果我们罗列10以下的能被3或5整除的自然数,我们可以得到3,5和9.他们的和为23.
请计算出1000以下能被3和5整除的自然数之和是多少?
Problem 2
Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 1 and 2, the first 10 terms will be:
1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ...
Find the sum of all the even-valued terms in the sequence which do not exceed four million.
斐波纳契数列每一个值是由前两个数值相加和成.从1和2开始.前10个值为:
1,2,3,5,8,13,21,34,55,89,...
请计算出不超过4百万的值中的各个数值之和.