A109135 Least number whose n-th power is exclusionary (or 0 if no such n exists). An exclusionary n-th power m^n is one made up of digits not appearing in m, which itself consists of distinct digits.

0, 2, 2, 2, 0, 2, 3, 3, 0, 3, 3, 2, 0, 2, 0, 2, 0, 0, 3, 2, 0, 2, 2, 7, 0, 2, 3, 3, 0, 0, 0, 0, 0, 2, 2, 2, 0, 0, 2, 3, 0, 2, 0, 0, 0, 2, 0, 0, 0, 3, 0, 0, 0, 2, 3, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 2, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0

Offset

2,2

Comments

a(n)=0 for n=1(mod 4)=A016813.

a(4k+1) = 0. All other zeros are unproved and have been checked up to m = 1000. - David Wasserman, May 27 2008

References

H. Ibstedt, Solution to Problem 2623, "Exclusionary Powers", pp. 346-9 Journal of Recreational Mathematics, Vol. 32 No.4 2003-4 Baywood NY.

Links

Table of n, a(n) for n=2..106.

Crossrefs

Cf. A113951.

Sequence in context: A216265 A336694 A130277 * A264136 A274850 A349437

Adjacent sequences: A109132 A109133 A109134 * A109136 A109137 A109138

Keyword

less,nonn,base

Author

Lekraj Beedassy, Aug 17 2005

Extensions

More terms from David Wasserman, May 27 2008

Status

approved