A081609 Number of numbers <= n having at least one 1 in their ternary representation.

0, 1, 1, 2, 3, 4, 4, 5, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 14, 15, 15, 16, 17, 18, 18, 19, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 46, 47, 47, 48, 49, 50, 50, 51, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 60, 61

Offset: 0

Author

Reinhard Zumkeller, Mar 23 2003

Keywords

• nonn

Comments

a(n) + A061392(n) = n+1.

Crossrefs

Cf. A007089, A062756, A081607, A081610, A061392.

Partial sums of A316829.

Programs

PARI

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