A129846 Numbers k such that k and 3*k share at least one digit.

5, 10, 13, 14, 15, 17, 20, 24, 25, 28, 30, 31, 35, 40, 41, 42, 45, 47, 48, 49, 50, 51, 52, 53, 55, 56, 57, 60, 61, 62, 65, 70, 71, 72, 75, 79, 80, 82, 85, 86, 90, 92, 93, 95, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 110, 113, 114, 115, 117, 120, 123, 124, 125

Offset: 1

Author

Eric Angelini, May 22 2007

Keywords

• base
• easy
• nonn
• changed

Links

• Robert Israel, Table of n, a(n) for n = 1..10000

Crossrefs

Complement of A140467.

Programs

Maple

a:=proc(n) if nops(convert(convert(n,base,10),set) intersect convert(convert(3*n,base,10),set))>0 then n else fi end: seq(a(n),n=1..145); # Emeric Deutsch, May 27 2007

Mathematica

Select[Range[300],Length[Intersection[IntegerDigits[ # ],IntegerDigits[3*# ]]] > 0 &] (* Stefan Steinerberger, May 24 2007 *)

Extensions

More terms from Stefan Steinerberger and Emeric Deutsch, May 24 2007