

A131617


Numbers n such that decimal expansion of 3^n contains no 5.


1



0, 1, 2, 3, 4, 5, 6, 7, 9, 11, 14, 15, 16, 17, 18, 19, 20, 23, 25, 29, 31, 41, 44, 52, 58, 81, 91
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OFFSET

1,3


COMMENTS

I conjecture that 91 is the last term.


LINKS

Table of n, a(n) for n=1..27.


MATHEMATICA

Join[{0}, Select[ Range@10000, FreeQ[ IntegerDigits[3^# ], 5] &]


PROG

(MAGMA) [n: n in [0..1000]  not 5 in Intseq(3^n) ]; // Vincenzo Librandi, May 06 2015


CROSSREFS

Cf. similar sequences listed in A131613.
Cf. A007377.
Sequence in context: A030151 A283455 A283364 * A214321 A320318 A005577
Adjacent sequences: A131614 A131615 A131616 * A131618 A131619 A131620


KEYWORD

base,fini,nonn


AUTHOR

Shyam Sunder Gupta, Sep 01 2007


EXTENSIONS

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


STATUS

approved



