A062891 When expressed in base 3 and then interpreted in base 9, is a multiple of the original number.

0, 1, 2, 3, 6, 9, 13, 18, 26, 27, 34, 39, 47, 54, 78, 81, 91, 102, 117, 121, 141, 162, 182, 234, 242, 243, 262, 273, 306, 351, 363, 423, 486, 546, 702, 726, 729, 757, 786, 819, 918, 1048, 1053, 1089, 1093, 1183, 1269, 1458, 1514, 1638, 2106, 2178, 2186, 2187

Offset

1,3

Links

Harvey P. Dale, Table of n, a(n) for n = 1..751 [offset shifted by Georg Fischer, Jun 15 2021]

Example

13 in base 3 is 111, which interpreted in base 9 is 91 = 7*13.

Maple

q:= n-> (l-> n=0 or 0=irem(add(l[i]*9^(i-1),
         i=1..nops(l)), n))(convert(n, base, 3)):
select(q, [$0..3000])[];  # Alois P. Heinz, Apr 20 2021

Mathematica

Join[{0}, Select[Range[2200], Divisible[FromDigits[IntegerDigits[#, 3], 9], #]&]] (* Harvey P. Dale, Apr 11 2017 *)

Crossrefs

Cf. A007089 (base 3), A007095 (base 9), A037314 (base 3 -> 9).

Other digit spreads: A062846 (binary), A343550 (decimal).

Sequence in context: A190772 A130673 A306777 * A018599 A325340 A018347

Adjacent sequences: A062888 A062889 A062890 * A062892 A062893 A062894

Keyword

base,nonn

Author

Erich Friedman, Jul 21 2001

Extensions

Offset changed to 1 by Kevin Ryde, Apr 24 2021

Status

approved