Let a1, a2 ..., an be a given A.P. whose common difference is an integer and Sn = a1 + a2 + ..+ an. If a1 = 1, an = 300 and 15 ≤ n ≤ 50, then the ordered pair (Sn – 4, an – 4) is equal to :
o (2480, 249)
o (2490, 249)
o (2490, 248)
o (2480, 248)