The sum up to 60 terms of `3/(1^2) + 5/(1^2 + 2^2) + 7/(1^2 + 2^2 + 3^2) + …….` is equal to

The sum to 50 terms of the series 3/1^2+5/(1^2+2^2)+7/(1^+2^2+3^2)+….+… is

The nth term of the given sequence 3/ (1^ 2) ⋅ 5/ (1^ 2 + 2^ 2) ⋅ 7/ (1^ 2 + 2^ 2 + 3^ 2) ⋅ 9/ (1^ 2 + 2^ 2 + 3^ 2 + 4^ 2)

The sum to 50 terms of series (3)/(1^(2))+(5)/(1^(2)+2^(2))+(7)/(1^(2)+2^(2)+3^(2))+...... is equal to

The sum of the series (3)/(1^(2))+(5)/(1^(2)+2^(2))+(7)/(1^(2)+2^(2)+3^(2))+... is

Let S_(n) be the sum to n terms of the series (2)/(1 ^(2)) + (5)/(1 ^(2) + 2^(2)) + (7)/(1^(2) + 2^(2) + 3^(2)) + (9)/(1 ^(2) + 2^(2) + 3 ^(2) + 6 ^(2))+ ……. then

Sum of first 20 terms of (3)/(1^(2))+(5)/(1^(2)+2^(2))+(7)/(1^(2)+2^(2)+3^(2))+... upto 20 terms is :