a(n) is the smallest number k such that with x(1) = k and x(i+1) = 2*x(i) + 1, x(i+1) has exactly one more prime factor (counted with multiplicity) than x(i) for i = 1 to n but not i = n + 1.

A381502

a(n) is the smallest number k such that with x(1) = k and x(i+1) = 2*x(i) + 1, x(i+1) has exactly one more prime factor (counted with multiplicity) than x(i) for i = 1 to n but not i = n + 1.