A033862 Sorted number reached from starter n in Sort-then-add sequence, or -1 if never reaches sorted number.

1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 11, 12, 13, 14, 15, 16, 17, 18, 19, 22, 33, 22, 23, 24, 25, 26, 27, 28, 29, 33, 44, 55, 33, 34, 35, 36, 37, 38, 39, 44, 55, 66, 77, 44, 45, 46, 47, 48, 49, 55, 66, 77, 88, 99, 55, 56, 57, 58, 59, 66, 77, 88, 99, 233, 233, 66, 67, 68, 69, 77, 88

Offset

1,2

Comments

Probably a(316) = -1.

Links

Michael S. Branicky, Table of n, a(n) for n = 1..315

Eric Weisstein's World of Mathematics, Sort-then-Add Sequence.

Prog

(Python)
from itertools import islice
def a(n):
    while n != (s:=int("".join(sorted(str(n))))): n += s
    return s
print([a(n) for n in range(1, 72)]) # Michael S. Branicky, Jan 15 2024

Crossrefs

Sequence in context: A340835 A123241 A355222 * A329201 A262038 A265558

Adjacent sequences: A033859 A033860 A033861 * A033863 A033864 A033865

Keyword

nonn,base

Author

David W. Wilson

Status

approved