A134026 Numbers that are in balanced ternary representation longer than in ternary representation.

2, 5, 6, 7, 8, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131

Offset: 1

Author

Reinhard Zumkeller, Oct 19 2007

Keywords

• nonn
• base

Comments

A157671 is a subsequence. - Reinhard Zumkeller, Jan 20 2010

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000

Crossrefs

Complement of A134025.

Cf. A081604, A134021, A157671, A171960.

Programs

Mathematica

Select[Range[150], Ceiling[Log[3, 2*#+1]] > IntegerLength[#, 3] &] (* Amiram Eldar, Apr 03 2025 *)

Formula

a(n) = g(n,0,0) with g(n,m,k) = if n=0 then k else if k=3^m-1 then g(n-1,m,3*(k+1)/2+1) else g(n-1,m,k+1).

A134021(a(n)) = A081604(a(n)) + 1.

A171960(a(n)) < a(n). - Reinhard Zumkeller, Jan 20 2010