Question

Write a recursive formula for the sequence 15, 26, 48, 92, 180, …. Then find the next term.

Answer 1

26 - 15 = 1 * 11
48 - 26 = 22 = 2 * 11
92 - 48 = 44 = 4 * 11
180 - 92 = 88 = 8 * 11

Answer 2

\[a _{n}=2a _{n-1}-4\]

Answer 3

\(a_1 = 15\)

\(a_2 = a_1 + 11(2 - 1)\)

\(a_3 = a_2 + 11(3 - 1) \)

\(a_n = a_{n - 1} + 11(n - 1)\)

Answer 4

Thank you so much!!

Answer 5

\[a _{n}=11*2^n+4,n \in I,n \ge 0\]