67644domain: NAppears in sequencesMaximum cycle size in range [A014137(n-1)..A014138(n-1)] of permutation A071665/A071666.at n=17A089874Numbers k whose trajectory under the Reverse and Add! operation carried out in base 16 does not reach a palindrome and (presumably) does not join the trajectory of any term m < k.at n=31A344119