The sum of series
`1+6+(9(1^(2)+2^(2)+3^(2)))/(7) + (12(1^(2)+2^(2)+3^(2)+4^(2)))/(9)+(15(1^(2)+2^(2)+...+5^(2)))/(11)+...` up to 15 terms is

The sum (3)/(1^(2)) + (5)/(1^(2) + 2^(2)) + (7)/(1^(2)+ 2^(2) + 3^(2)) + ….. upto 11 terms is

Find sum of first 15 term of series 1+6+(9(1^(2)+2^(2)+3^(2)))/(7)+(12(1^(2)+2^(2)+3^(2)+4^(2)))/(9) (1) 7620 (2) 7280 (3) 7820 (4) 7067

The sum to n terms of the series (3)/(1^(2))+(5)/(1^(2)+2^(2))+(7)/(1^(2)+2^(2)+3^(2))+--

The sum of n terms of the series 1^(2) - 2^(2) + 3^(2)- 4^(2) + 5^(2) -6^(2) + ….is

the sum (3)/(1^(2))+(5)/(1^(2)+2^(2))+(7)/(1^(2)+2^(2)+3^(2))+...... upto 11 terms

(1^(2)-2^(2)+3^(2)) + (4^(2)-5^(2)+6^(2))+(7^(2)-8^(2)+9^(2))….30 terms

(1^(2)-2^(2)+3^(2)) + (4^(2)-5^(2)+6^(2))+(7^(2)-8^(2)+9^(2))….30 terms

The sum of n terms of the series 1^(2)-2^(2)+3^(2)-4^(2)+5^(2)-6^(2)+... is

The sum of the series 1+ 2/3+ (1)/(3 ^(2)) + (2 )/(3 ^(3)) + (1)/(3 ^(4)) + (2)/(3 ^(5)) + (1)/(3 ^(6))+ (2)/(3 ^(7))+ …… upto infinite terms is equal to :