OFFSET
1,2
COMMENTS
The sequence is finite; after twelve terms 18 is reached which has no following term - see A367341.
EXAMPLE
a(6) = 78 as a(5) = 135, and |78 - 135| = 57 which can be formed from the last digit of 135 and the first digit of 78.
a(12) = 18 as a(11) = 109, and |18 - 109| = 91 which can be formed from the last digit of 109 and the first digit of 18. See A367341 for a proof that no following term can exist.
CROSSREFS
KEYWORD
nonn,fini,full,base
AUTHOR
Scott R. Shannon and Eric Angelini, Nov 25 2023
STATUS
approved