cp's OEIS Frontend

A030106 Base 7 reversal of n (written in base 10).

%I A030106 #23 May 20 2020 02:58:50
%S A030106 0,1,2,3,4,5,6,1,8,15,22,29,36,43,2,9,16,23,30,37,44,3,10,17,24,31,38,
%T A030106 45,4,11,18,25,32,39,46,5,12,19,26,33,40,47,6,13,20,27,34,41,48,1,50,
%U A030106 99,148,197,246,295,8,57,106,155,204,253,302,15,64,113,162,211,260,309,22,71
%N A030106 Base 7 reversal of n (written in base 10).
%H A030106 Robert Israel, <a href="/A030106/b030106.txt">Table of n, a(n) for n = 0..10000</a>
%p A030106 f:= proc(n) local L,k;
%p A030106   L:= convert(n,base,7);
%p A030106   add(L[-i]*7^(i-1),i=1..nops(L))
%p A030106 end proc:
%p A030106 map(f, [$0..100]); # _Robert Israel_, May 19 2020
%t A030106 Table[FromDigits[Reverse[IntegerDigits[n,7]],7],{n,0,80}] (* _Harvey P. Dale_, Sep 17 2013 *)
%o A030106 (PARI) a(n,b=7)=subst(Polrev(base(n,b)),x,b) /* where */
%o A030106 base(n,b)={my(a=[n%b]);while(0<n\=b,a=concat(n%b,a));a}  \\ _M. F. Hasler_, Nov 04 2011
%Y A030106 Cf. A030101 - A030108, A004086.
%K A030106 nonn,base,look
%O A030106 0,3
%A A030106 _David W. Wilson_