A061944 - OEIS

%I #19 Dec 05 2020 10:41:08

%S 1,3,5,7,28,48,143,148,224,392,2079,2716,2999,12537,14392,16384,32124,

%T 52073,56747,138203,238847,527989,4580376,5147667,5276712,6982808,

%U 8947484

%N Numbers n such that n divides the (right) concatenation of all numbers <= n written in base 15 (most significant digit on right).

%C This sequence differs from A029508 in that all least significant zeros are removed before concatenation.

%C No more terms < 10^7. - _Lars Blomberg_, Oct 22 2011

%H <a href="/index/N#concat">Index entries for related sequences</a>

%e See A061931 for example.

%t b = 15; c = {}; Select[Range[10^4], Divisible[FromDigits[c = Join[c, IntegerDigits[IntegerReverse[#, b], b]], b], #] &] (* _Robert Price_, Mar 08 2020 *)

%o (PARI) lista(nn, m=15) = my(s, t); for(k=1, nn, s=k/m^valuation(k, m); while(s, t=t*m+s%m; s\=m); if(t%k==0, print1(k, ", "))); \\ _Jinyuan Wang_, Dec 05 2020

%Y Cf. A029447-A029470, A029471-A029494, A029495-A029518, A029519-A029542, A061931-A061954, A061955-A061978.

%K nonn,base,more

%O 1,2

%A Larry Reeves (larryr(AT)acm.org), May 24 2001

%E Edited and updated by Larry Reeves (larryr(AT)acm.org), Apr 12 2002; Aug 25 2002

%E a(23)-a(27) from _Lars Blomberg_, Oct 22 2011