IMO 1969 LL SWE61

Let a0, a1, a2 be determined with a0 = 0, an+1 = 2an + 2n.

IMO 1969 LL SWE61

Origin: SWE

Problem

Let a0, a1, a2 be determined with a0 = 0, an+1 = 2an + 2n. Prove that if n is power of 2, then so is an.