login
A259043
a(n) = if n < 10 then n else a(floor(n/10) + n mod 10) + n mod 10.
2
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 3, 5, 7, 9, 11, 13, 15, 17, 10, 2, 4, 6, 8, 10, 12, 14, 16, 9, 12, 3, 5, 7, 9, 11, 13, 15, 8, 11, 14, 4, 6, 8, 10, 12, 14, 7, 10, 13, 16, 5, 7, 9, 11, 13, 6, 9, 12, 15, 18, 6, 8, 10, 12, 5, 8, 11, 14, 17, 20, 7, 9, 11, 4, 7
OFFSET
0,3
COMMENTS
a(A259046(n)) = n and a(m) != n for m < A259046(n).
LINKS
PROG
(Haskell)
a259043 x = if x < 10 then x else a259043 (x' + d) + d
where (x', d) = divMod x 10
(PARI) a(n) = if (n<10, n, my(u=n%10); a(n\10 + u) + u); \\ Michel Marcus, Jan 23 2022
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Jun 17 2015
STATUS
approved