OFFSET
1,2
COMMENTS
The sequence starts with a(1) = 1 and is always extended with the smallest integer not yet present that doesn't lead to a contradiction.
LINKS
Hans Havermann, Table of n, a(n) for n = 1..1000
Hans Havermann, Graph of the first 100000 terms
EXAMPLE
1 = a(1) is replaced by 1 + 10 = 11
12 = a(2) is replaced by 12 + 10 = 22
2 = a(3) is replaced by 2 + 10 = 12
121 = a(4) is replaced by 121 + 10 = 131
3 = a(5) is replaced by 3 + 10 = 13
11 = a(6) is replaced by 11 + 10 = 21
32 = a(7) is replaced by 32 + 10 = 42
14 = a(8) is replaced by 14 + 10 = 24
etc.
We see that the first and the last column here (which are respectively the terms of the present sequence and the terms of the transformed one) share the same succession of digits (so far): 1,1,2,2,1,2,1,3,1,1,3,2,1,4,2,2,4,...
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Eric Angelini and Hans Havermann, Apr 13 2018
STATUS
approved