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Numbers that, when expressed in base 3 and then interpreted in base 10, yield a multiple of the original number.
3

%I #35 Feb 25 2024 05:57:37

%S 0,1,2,7,14,15,21,38,91,132,182,203,210,273,392,420,546,637,924,1365,

%T 1526,1658,1911,1974,2730,3030,3367,4095,5733,6734,7035,10101,20202,

%U 21105,22748,30303,44702,49308,68432,107744,112854,129990,205296

%N Numbers that, when expressed in base 3 and then interpreted in base 10, yield a multiple of the original number.

%H Giovanni Resta, <a href="/A032537/b032537.txt">Table of n, a(n) for n = 1..136</a> (terms < 10^12, first 101 terms from Paolo P. Lava)

%e 7 in base 3 is 21, which interpreted in base 10 is 21=3*7.

%t lst = {0}; Do[If[Mod[FromDigits[IntegerDigits[n, 3]], n] == 0, AppendTo[lst, n]], {n, 10000}]; lst (* _Carl Najafi_, Aug 21 2011 *)

%Y Cf. A032536, A032538.

%K nonn,base

%O 1,3

%A _Patrick De Geest_, Apr 15 1998

%E Example and better description from _Erich Friedman_, Jul 21 2001

%E Edited by _Erich Friedman_ Feb 09 2002

%E Offset set to 1 by _Giovanni Resta_, Jul 13 2016

%E Name edited by _Jon E. Schoenfield_, Oct 25 2019