OFFSET
0,12
COMMENTS
A companion sequence to A320486.
Digits that appear exactly once in n are erased. Leading zeros are erased unless the result is 0. If all digits are erased, we write 0 for the result (A321800 is another version, which uses -1 for the empty string).
More than the usual number of terms are shown in order to reach some interesting examples.
LINKS
Chai Wah Wu, Table of n, a(n) for n = 0..10000
EXAMPLE
12321 becomes 1221, 1123 becomes 11, 11231 becomes 111, and 100223 becomes 22 (as we don't accept leading zeros). Note that 12345 disappears immediately and we get 0.
PROG
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Chai Wah Wu, Nov 19 2018
STATUS
approved