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PROJECT EULER · #0012

Highly Divisible Triangular Number

Statement only · SolvedOriginal problem ↗

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:

1:13:1,36:1,2,3,610:1,2,5,1015:1,3,5,1521:1,3,7,2128:1,2,4,7,14,28

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?

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