cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A323975 a(n) sets a new record for the Lychrel number a(n) of 'Reverse and Add' steps, needed to reach a Lychrel number m < a(n) (i.e., its seed).

Original entry on oeis.org

195, 295, 4799, 10653, 10821, 14995, 105985, 1005523, 1008927, 1009413, 1029983
Offset: 1

Views

Author

A.H.M. Smeets, Feb 10 2019

Keywords

Comments

Records in A323976.
Similar to the number of steps needed to reach a palindrome in the Reverse and Add! trajectories (see A065198 and A065199), the number of steps needed for a Lychrel number to reach the trajectory of its seed is relatively small.

Crossrefs

Cf. A065198, A065199, A323976.

A344119 Numbers 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.

Original entry on oeis.org

413, 429, 443, 445, 3407, 3647, 3711, 3775, 3807, 3839, 4287, 7417, 12463, 12527, 16383, 24575, 28879, 45183, 45231, 49151, 57343, 61615, 61663, 61679, 66511, 66783, 67023, 67535, 67551, 67628, 67630, 67644, 67646, 67673, 67674, 67676, 67688, 67718, 67734
Offset: 1

Views

Author

A.H.M. Smeets, Aug 16 2021

Keywords

Comments

A number is considered here (presumably) a Lychrel number in base 16 if it does not reach a palindrome within 200 steps more than the actual record. Those record numbers of steps to become palindromic are known from data in other bases not to increase that much (see for instance A065198 and A065199 in case of base 10). Furthermore, a Lychrel number is considered not to reach the trajectory of any smaller Lychrel number if it does not reach a trajectory of a smaller Lychrel number within 100 steps more than the actual record. Again, those record numbers of steps to reach the trajectory of a smaller Lychrel number are known from data in other bases not to increase that much (see for instance A323975 and A323976 in case of base 10).

Crossrefs

In other bases: A075252 (2), A077405 (3), A075421 (4), A306596 (8), A063048 (10).
Cf. A065198, A065199, A323975, A323976.
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Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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