
William W. answered 02/20/21
Math and science made easy - learn from a retired engineer
For n = 1, A1 = 1
For n = 2, A2 = 2A1 + 2 = 2(1) + 2 = 4
For n = 3, A3 = 2A2 + 3 = 2(4) + 3 = 11
For n = 4, A4 = 2A3 + 4 = 2(11) + 4 = 26
For n = 5, A5 = 2A4 + 5 = 2(26) + 5 = 57
For n = 6, A6 = 2A5 + 6 = 2(57) + 6 = 120