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A062891
When expressed in base 3 and then interpreted in base 9, is a multiple of the original number.
13
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: A130673 A374702 A306777 * A018599 A325340 A018347
KEYWORD
base,nonn
AUTHOR
Erich Friedman, Jul 21 2001
EXTENSIONS
Offset changed to 1 by Kevin Ryde, Apr 24 2021
STATUS
approved