for loop - How to express this sum concisely in R? -

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i have simple r beginner's question:

how express sum below concisely in r?

sum_{i=1}^n / (a+i)

i tried following, there must better way, without calling for:

r<-0 for(i in 1:n){ r <- r + (a / (a+i)) }

thanks!

i believe it's simple as:

sum(a/(a+1:n))

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