Re: [math-fun] Another puzzle

On 23 Jan 2012, David Wilson asked:

What n satisfy 2^n == 3n+2 (mod n^2 - 2n)

At first glance, except for n=5, these appear to be the greater of twin primes (A006512). However, on closer inspection, some n (563, 645, 647, 1105, 1907, 2467, 2701, 2821, 4371, 4373, 4681, 6601, ...) are clearly not.