1410123943domain: NAppears in sequences'3x+1' record-setters (blowup factor).at n=27A025587Numbers n such that at least one member of Collatz (3x+1) trajectory of n is >= n^2.at n=40A225038In the Collatz (3x+1) problem, values in A006884 for which the maximum excursion ratio (see comments) is greater than 2.at n=2A365482