91466domain: NAppears in sequencesa(n) is the least number k such that prime(k) - 1 is divisible by 2^(n-1) and the quotient is odd.at n=17A057776Indices of primes of the form 2^t*3^u + 1 in the primes.at n=42A174099Indices of primes of the form p = 2^i + 2^j + 1, i > j > 0 (A081091).at n=46A360448