1,1

For 318 (cf. A075153), 266718 (cf. A075466) and 270798 (cf. A075467) one can prove that the base 4 trajectory does not contain a palindrome. A proof for 290 (cf. A075299) has not been found up to now. 4398859679359 is another known candidate (obtained from a remark of David Seal, cf. Links) for a term whose trajectory is provably palindrome-free, but is not secured that it does not join the trajectory of some term m < n. - If the trajectory of an integer k joins the trajectory of a smaller integer which is a term of the present sequence, then this occurs after very few Reverse and Add! steps (at most 28 for k < 20000). On the other hand, the trajectories of the terms listed above do not join the trajectory of any smaller term within at least 1000 steps.

Base 4 analogue of A063048 (base 10) and A075252 (base 2); subsequence of A075420.

Klaus Brockhaus, Illustration: Distribution of terms below 2000000

D. Seal, Results

Index entries for sequences related to Reverse and Add!

719 is a term since the trajectory of 719 (presumably) does not lead to an integer which occurs in the trajectory of 290 or of 318.

Cf. A063048, A075252, A075420, A075299, A075153, A075466, A075467, A091675.

Sequence in context: A091680 A129245 A075420 this_sequence A090839 A158255 A075299

Adjacent sequences: A075418 A075419 A075420 this_sequence A075422 A075423 A075424

base,nonn

Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Sep 18 2002, revised Jan 28 2004