Pls explain 1)an rearrangement be done only once in series or can we do several times as per our choice and 2) can rearrangement be done only in absolutely conv

if series is conditionally convergent then we can rearranged to get desired sum

any doubt in this?

.

any doubt please ask

sir is series 1+2+3...+infinity absolutely convergent...if no. pls help how ramanujan found its sum equal to 1/12

not convergent..

ramanujan sum is different thing , summation n is divergent..

see this series is always divergent

read this carefully

ramanujan series is not sum of series..

https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.quora.com/Does-the-sum-of-all-positive-integers-equal-1-12&ved=2ahUKEwjFh8Lgp9zqAhW-73MBHYOqAz0QjjgwEnoECAYQAQ&usg=AOvVaw2xTs0KxCEQ5Qmd1uaFZnMj&cshid=1595265240976

go through above link .. if any doubt please ask

ramanujan sum was discovered at old time , they don't know that they are subtracting infinite series.. later on it was develoed and now known as ramanujan zeta function , which is concept of higher physics

thanks a lot sir..

sir is series 1+2+3...+infinity absolutely convergent...if no. pls help how ramanujan found its sum equal to 1/12

first thing is that at that time there is no such concept. secondly this is not an convergent series. at that time no one think about that they are subtracting infinite from infinite (you will find in its proof) which no one notice at that time that he is actually deal with indeterminate

actually the way by which he find -1/12 was amaze and due to lack of knowledge at that time no one notice mistakes done by him. you can search on you tube and find such videos which tells you that

thank a lot sir