Math
posted by Bob .
I need help with making a formula..?
This is what I put..
"The 100th Triangular Number is 5,050. I found this by adding 100 to the value of the 99th Triangular Number. The 99th Triangular Number is 4,950. The formula I used to find it is..."
Help?

I provided the formula in response to a previous post about triangle numbers.
Once again, it is N(N+1)/2
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