

A087553


Squares in which the neighboring digits differ at most by 1. Neighbors of 1 are 0 and 2, neighbors of 0 are 1 and 9.


0



1, 4, 9, 100, 121, 676, 900, 10000, 12100, 12321, 90000, 1000000, 1210000, 1232100, 1234321, 9000000, 100000000, 121000000, 123210000, 123432100, 123454321, 900000000, 10000000000, 11122233444, 12100000000, 12321000000, 12343210000
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OFFSET

0,2


COMMENTS

The sequence is infinite with trivial terms like 10^(2k) and 9*10^(2k). Conjecture: There are infinitely many nontrivial terms.


LINKS



EXAMPLE

12321, 1345678987654321 are members.


CROSSREFS



KEYWORD

base,nonn


AUTHOR



EXTENSIONS



STATUS

approved



