

A131613


Numbers k such that the decimal expansion of 3^k contains no 9.


8



0, 1, 3, 4, 5, 7, 8, 11, 12, 16, 19, 20, 21, 29, 32, 56
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OFFSET

1,3


COMMENTS

I conjecture that 56 is the last term.


LINKS

Table of n, a(n) for n=1..16.


MATHEMATICA

Join[{0}, Select[ Range@10000, FreeQ[ IntegerDigits[3^# ], 9] &]]


PROG

(Magma) [n: n in [0..1000]  not 9 in Intseq(3^n) ]; // Vincenzo Librandi, May 06 2015


CROSSREFS

Numbers k such that the decimal expansion of 3^k contains no m: A030700 (m=0), A131627 (m=1), A131625 (m=2), A131629 (m=3), A131618 (m=4), A131617 (m=5), A131616 (m=6), A131615 (m=7), A131614 (m=8), this sequence (m=9).
Cf. A007377.
Sequence in context: A047500 A359822 A257408 * A138494 A285531 A111801
Adjacent sequences: A131610 A131611 A131612 * A131614 A131615 A131616


KEYWORD

base,fini,nonn


AUTHOR

Shyam Sunder Gupta, Sep 01 2007


EXTENSIONS

Adapted Mma and initial 0 added by Vincenzo Librandi, May 06 2015


STATUS

approved



