cp's OEIS Frontend

A330164 Even perfect numbers w from A000396 such that number m = w / 2^(k(w) - 1) - 2^((k(w) - 1)/2) + 1 = 2^k(w) - 2^((k(w) - 1)/2) is also an even perfect number, where k(w) is the Mersenne exponent (A000043) for number w.