

A030703


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


26




OFFSET

1,3


COMMENTS

No additional terms up to 20,000.  Harvey P. Dale, Oct 02 2013


LINKS

Table of n, a(n) for n=1..10.
W. Schneider, NoZeros: Powers n^k without Digit Zero [Cached copy]
Eric Weisstein's World of Mathematics, Zero


FORMULA

A030703 = A000420^(1)(A052382) as a set, where f^(1)(Y) = { x : f(x) in Y}.
A030703 = A000420^(1) o A195908 as a function.  M. F. Hasler, Sep 25 2011


MATHEMATICA

Select[Range[0, 100], DigitCount[7^#, 10, 0]==0&] (* Harvey P. Dale, Oct 02 2013 *)


PROG

(PARI) for( n=0, 9999, is_A052382(7^n) && print1(n, ", ")) \\ M. F. Hasler, Sep 25 2011
(MAGMA) [n: n in [0..500]  not 0 in Intseq(7^n)]; // Vincenzo Librandi, Mar 08 2014


CROSSREFS

Cf. A195942, A195943, A195944, A195945, A195946, A195908, A007377, A008839, A030700, A030701, A030702, A030704, A030705, A030706.
Sequence in context: A278965 A032858 A181498 * A305927 A271585 A285259
Adjacent sequences: A030700 A030701 A030702 * A030704 A030705 A030706


KEYWORD

nonn,base


AUTHOR

Eric W. Weisstein


EXTENSIONS

Added initial term 0.  M. F. Hasler, Sep 25 2011


STATUS

approved



