OFFSET
0,2
COMMENTS
It is conjectured that all iterations of this sequence starting from any n >= 0 will eventually reach a finite cycle, which by necessity then contains at least one multiple of three. See Drozd links and A349876.
LINKS
Antti Karttunen, Table of n, a(n) for n = 0..19683
Nicholas Drozd, A Busy Beaver Champion Derived from Scratch
Nicholas Drozd, Feedback to Doron Zeilberger's opinion #155, Jan. 4, 2022
PROG
(PARI) A353313(n) = { my(r=(n%3)); if(!r, n/3, ((5*((n-r)/3)) + r + 3)); };
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Apr 13 2022
STATUS
approved