Categoty :
elaine : Find the sum of the first 20 terms of the A.P. whose n^th term is given by a_n = 1 + 13n.

	: Find the sum of the first 20 terms of the A.P. whose n^th term is given by a_n = 1 + 13n.
	180#0#280#0#90#0#233 #0#