2
2 × 4 - 1 = 7
7 × 4 - 1 = 27
27 × 4 - 1 = 107
107 × 4 - 1 = 427
427 × 4 - 1 = 1707
What will come in place of the x in the following Number series? 2, 7, 27, 107, 427, x
[1] 1427
[2] 1607
[3] 1707
[4] 2047
[5] 2147