%I A053833
%S A053833 0,1,2,3,4,5,6,7,8,9,10,11,12,1,2,3,4,5,6,7,8,9,10,11,12,13,2,3,4,5,6,
%T A053833 7,8,9,10,11,12,13,14,3,4,5,6,7,8,9,10,11,12,13,14,15,4,5,6,7,8,9,10,
%U A053833 11,12,13,14,15,16,5,6,7,8,9,10,11,12,13,14,15,16,17,6,7,8,9,10,11,12
%N A053833 Sum of digits of n written in base 13.
%C A053833 a(n) = A138530(n,13) for n > 12. - Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), 
               Mar 26 2008
%H A053833 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               DigitSum.html">Digit Sum</a>
%F A053833 a(0)=0, a(13n+i)=a(n)+i 0<=i<=12; a(n)=n-12*(sum(k>0, floor(n/13^k)). 
               - Benoit Cloitre, Dec 19, 2002
%e A053833 a(20)=1+7=8 because 20 is written as 17 base 13
%o A053833 (PARI) a(n)=if(n<1,0,if(n%13,a(n-1)+1,a(n/13)))
%Y A053833 Cf. A000120, A007953.
%Y A053833 Sequence in context: A121759 A072778 A034326 this_sequence A087999 A106614 
               A043272
%Y A053833 Adjacent sequences: A053830 A053831 A053832 this_sequence A053834 A053835 
               A053836
%K A053833 base,nonn
%O A053833 0,3
%A A053833 Henry Bottomley (se16(AT)btinternet.com), Mar 28 2000