A131616 Numbers k such that the decimal expansion of 3^k contains no 6.

0, 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 15, 18, 23, 32, 35, 42, 55, 104

Offset: 1

Author

Shyam Sunder Gupta, Sep 01 2007

Keywords

• base
• fini
• nonn

Comments

I conjecture that 104 is the last term.

Crossrefs

Cf. similar sequences listed in A131613.

Cf. A007377.

Programs

Magma

[n: n in [0..1000] | not 6 in Intseq(3^n) ]; // Vincenzo Librandi, May 06 2015

Mathematica

Join[{0}, Select[ Range@10000, FreeQ[ IntegerDigits[3^# ], 6] &]]

Extensions

Initial 0 added and Mathematica code adapted by Vincenzo Librandi, May 06 2015