Question

the sum to n terms of the series 1+(1+2)+(1+2+3)+.....will be

Answer 1

1+2+3+4+.........+up to n terms= n(n+1)/2

Answer 2

Input : n = 5

Output : 35

Explanation :

(1) + (1+2) + (1+2+3) + (1+2+3+4) + (1+2+3+4+5) = 35

Input : n = 10

Output : 220

Explanation :

(1) + (1+2) + (1+2+3) + .... +(1+2+3+4+.....+10) = 220

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