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Decimal expansion of 7^n contains no zeros (probably finite).
26

%I #29 Jun 26 2022 05:41:58

%S 0,1,2,3,6,7,10,11,19,35

%N Decimal expansion of 7^n contains no zeros (probably finite).

%C No additional terms up to 20000. - _Harvey P. Dale_, Oct 02 2013

%H W. Schneider, <a href="/A007496/a007496.html">NoZeros: Powers n^k without Digit Zero</a> [Cached copy]

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Zero.html">Zero</a>

%F A030703 = A000420^(-1)(A052382) as a set, where f^(-1)(Y) = { x : f(x) in Y}.

%F A030703 = A000420^(-1) o A195908 as a function. - _M. F. Hasler_, Sep 25 2011

%t Select[Range[0,100],DigitCount[7^#,10,0]==0&] (* _Harvey P. Dale_, Oct 02 2013 *)

%o (PARI) for( n=0, 9999, is_A052382(7^n) && print1(n, ", ")) \\ _M. F. Hasler_, Sep 25 2011

%o (Magma) [n: n in [0..500] | not 0 in Intseq(7^n)]; // _Vincenzo Librandi_, Mar 08 2014

%Y Cf. A195942, A195943, A195944, A195945, A195946, A195908, A007377, A008839, A030700, A030701, A030702, A030704, A030705, A030706.

%K nonn,base

%O 1,3

%A _Eric W. Weisstein_

%E Initial term 0 inserted by _M. F. Hasler_, Sep 25 2011