

A320516


Palindromic wing primes that are also Lychrel candidates.


0



7774777, 777767777, 77777677777, 99999199999, 1111118111111, 7777774777777, 111111181111111, 333333373333333, 77777777677777777, 99999999299999999, 9999999992999999999, 33333333333733333333333, 77777777777677777777777, 333333333333373333333333333
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OFFSET

1,1


COMMENTS

Lychrel candidates are natural numbers that seem unable to form a palindrome through the iterative process of repeatedly reversing its digits and adding the resulting numbers.
On January 23, 2017 a Russian schoolboy, Andrey S. Shchebetov, announced on his web site that he had found a sequence of the first 126 numbers (125 of them never reported before) that take exactly 261 steps to reach a 119digit palindrome. That sequence was published in the OEIS as A281506. The trajectory of the last number of that sequence, 1186061987030929990, under the "Reverse and Add!" operation was published separately in the OEIS as A281507.


LINKS

Table of n, a(n) for n=1..14.
Robert Liguori, Github project SequencePier


CROSSREFS

Cf. A077798, A000040, A023108, A281506, A281507.
Sequence in context: A258954 A273101 A124416 * A319809 A214194 A205657
Adjacent sequences: A320513 A320514 A320515 * A320517 A320518 A320519


KEYWORD

nonn,base


AUTHOR

Robert James Liguori, Oct 29 2018


EXTENSIONS

Seven terms inserted by Jon E. Schoenfield, Oct 31 2018
a(14) from Jon E. Schoenfield, Nov 01 2018


STATUS

approved



