自然数求和可生成三角数列.第七个三角数是1 + 2 + 3 + 4 + 5 + 6 + 7 = 28.前10个三角数列元素是:

1, 3, 6, 10, 15, 21, 28, 36, 45, 55, ...



下面列出前7个三角数及其整除数:

1: 1

3: 1,3

6: 1,2,3,6

10: 1,2,5,10

15: 1,3,5,15

21: 1,3,7,21

28: 1,2,4,7,14,28

可以看出,28是第一个有超过5个整除数的三角数.



那么,第一个有超过500个整除数的三角数是多少?-The sequence of triangle numbers is generated by adding the natural numbers. So the 7th triangle number would be 1+ 2+ 3+ 4+ 5+ 6+ 7 = 28. The first ten terms would be:



1, 3, 6, 10, 15, 21, 28, 36, 45, 55, ...



Let us list the factors of the first seven triangle numbers:



　　 1: 1

　　 3: 1,3

　　 6: 1,2,3,6

　　10: 1,2,5,10

　　15: 1,3,5,15

　　21: 1,3,7,21

　　28: 1,2,4,7,14,28



We can see that 28 is the first triangle number to have over five divisors.



What is the value of the first triangle number to have over five hundred divisors?