1+(1+4)+(1+4+7)+(1+4+7+10)....................................................+∞
What is the general term and summation of the series?

Question

1+(1+4)+(1+4+7)+(1+4+7+10)....................................................+∞
What is the general term and summation of the series?

perl · Answer

actually better to add these in parentheses

perl · Answer

= 1 + 5 + 12 + ..

perl · Answer

so you want to sum the series
1 + 5 + 12 + 22 + ... 
well the sum is obvious infinity

perl · Answer

this is a quadratic sequence
1,5,12,22, ...

anonymous · Answer

the terms in each parentheses forms an A. P, with the first term 1 and common difference 3.

perl · Answer

akitav, not quite, they keep increasing

perl · Answer

its a quadratic progression, not arithmetic

anonymous · Answer

I want to know the sum of 'n' terms of the series. And bye the way what is the general term?

perl · Answer

the general term is a pentagonal sequence

perl · Answer

perl · Answer

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