Rediscovering 1,3,6,10 . . .

1,3,6,10,15 . . . already exists. 1,3,6,10,15 . . . is the triangle series.
I didn't know that. I rediscovered it. I applied rational growth and made some formulas. So the series was rediscovered.
I found another thing yesterday. The square series 1,4,9,16,25 . . . relationship with 1,3,6,10,15 . . .
Subtracting term by term each of the numbers of square series with the triangle series creates a series of terms 0, another triangle series.
1 - 1 = 0
4 - 3 = 1
9 - 6 = 3
16 - 10 = 6
25 - 15 = 10.
and so on . . .