A081608 Number of numbers <= n having no 0 in their ternary representation.

0, 1, 2, 2, 3, 4, 4, 5, 6, 6, 6, 6, 6, 7, 8, 8, 9, 10, 10, 10, 10, 10, 11, 12, 12, 13, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 15, 16, 16, 17, 18, 18, 18, 18, 18, 19, 20, 20, 21, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 23, 24, 24, 25, 26, 26, 26, 26

Offset: 0

Author

Reinhard Zumkeller, Mar 23 2003

Keywords

• nonn

Comments

a(n) + A081607(n) = n+1.

Links

• Winston de Greef, Table of n, a(n) for n = 0..16383

Crossrefs

Cf. A007089, A077267, A061392, A081611.

Programs

Mathematica

Accumulate[Table[If[DigitCount[n,3,0]==0,1,0],{n,0,80}]] (* Harvey P. Dale, Oct 21 2024 *)

PARI

first(n)=my(s,t); vector(n,k, t=Set(digits(k,3)); s+=!!t[1]) \\ Charles R Greathouse IV, Sep 02 2015