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

The sequence of triangle numbers is generated by adding the natural numbers. So the 7^{th} 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?

### One Possible Solution: Go

package main import "fmt" import "math" func main() { counter := 0 TriangleNumber := 0 Switch := 1 for Switch >= 1 { counter++ TriangleNumber += counter if factors(TriangleNumber) > 500 { fmt.Println(TriangleNumber) Switch = 0 } } } func factors(n int) (facCount int) { facCounter := 0 k := int(math.Sqrt(float64(n))) for i := 1; i < k+1; i++ { if n%i == 0 { facCounter++ } } return facCounter * 2 }

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