0,3

a(n) = A138530(n,15) for n > 14. - Reinhard Zumkeller, Mar 26 2008

Table of n, a(n) for n=0..83.

Robert Walker, Self Similar Sloth Canon Number Sequences

Eric Weisstein's World of Mathematics, Digit Sum

a(0)=0, a(15n+i)=a(n)+i 0<=i<=14; a(n)=n-14*(sum(k>0, floor(n/15^k)). - Benoit Cloitre, Dec 19 2002

a(20) = 1 + 5 = 6 because 20 is written as "15" in base 15.

(PARI) a(n)=if(n<1, 0, if(n%15, a(n-1)+1, a(n/15)))

Cf. A000120, A007953.

Sequence in context: A080331 A297247 A167463 * A072965 A297248 A043274

Adjacent sequences: A053832 A053833 A053834 * A053836 A053837 A053838

base,nonn

Henry Bottomley, Mar 28 2000

approved