A030705 Numbers k such that the decimal expansion of 9^k contains no zeros (probably finite).

0, 1, 2, 3, 4, 6, 7, 12, 13, 14, 17, 34

Offset: 1

Author

Eric W. Weisstein

Keywords

• nonn
• base

Comments

Integers in A030700 / 2. - M. F. Hasler, Mar 07 2014

No more terms <= 10^5. - Georg Fischer, Mar 12 2020

Links

• Eric Weisstein's World of Mathematics, Zero

Crossrefs

Cf. A007377 (analog for 2^n), A030700 (3), A030701 (4), A008839 (5), A030702 (6), A030703 and A195908 (7), A030704 (8), A030706 and A195946 (11), A195944 and A195945 (13); A195942, A195943.

This is row 0 of A305929.

Cf. A035064.

Programs

Magma

[n: n in [0..500] | not 0 in Intseq(9^n)]; // Vincenzo Librandi, Mar 08 2014

Mathematica

Reap[For[n = 0, n < 100, n++, If[FreeQ[IntegerDigits[9^n], 0], Sow[n]]]][[2, 1]] (* Jean-François Alcover, Oct 04 2017 *)

PARI

select( is(n)=vecmin(digits(9^n)), [0..39]) \\ M. F. Hasler, Mar 07 2014

Extensions

Offset changed to 1 and initial 0 added by M. F. Hasler, Mar 07 2014

Removed keyword "fini" (as in A035064) since it is only a conjecture that this sequence contains only finitely many terms. - Georg Fischer, Mar 12 2020