A186703 Balanced ternary non-Harshad numbers.

2, 6, 8, 13, 16, 18, 20, 24, 26, 31, 32, 37, 41, 46, 48, 52, 54, 56, 60, 62, 67, 70, 72, 74, 78, 80, 85, 86, 91, 94, 96, 98, 103, 104, 109, 115, 118, 119, 121, 122, 125, 130, 131, 136, 138, 142, 144, 146, 149, 154, 156, 160

Offset: 1

Author

Alonso del Arte, Feb 25 2011

Keywords

• nonn
• base

Comments

Numbers not divisible by the sum of their balanced ternary digits.

All terms of A174658 are in this sequence because their balanced ternary digits add up to 0.

Terms of this sequence not in A174658 are generally prime numbers.

Examples

			The balanced ternary representation of 13 is {1, 1, 1}, which adds up to 3. Since 3 does not divide 13 evenly, 13 is in the list.
The balanced ternary representation of 17 is {1, -1, 0, -1}, this adds up to -1, which divides 17 evenly. Therefore, 17 is not in the list.
		

Crossrefs

Cf. A005349, base 10 Harshad numbers.

Programs

Mathematica

(* First run the program for A065363 to define balTernDigits *) Complement[Range[200], Select[Range[200], Plus@@balTernDigits[#] != 0 && IntegerQ[#/(Plus@@balTernDigits[#])] &]]