-99
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0,1,3,6,10,15,21,28,36,45,55,66,78,91
The Nth triangular number is calculated by: N(N + 1) -------- 2 Hope this is useful!
They are 105, 120, 136, 153, 171 and 190.
25 numbers are between 1-100.
Square: 1, 4, 9, 16, 25, 36, 49. Triangular: 1, 3, 6, 10, 15, 21, 28, 36, 45.