A124649 Numbers n such that n^i (i=1..8) are all zeroless.

1, 2, 3, 6, 68

Offset

1,2

Comments

No other terms < 10^6. Is the sequence finite?

Subsequence of A124648. No other terms below 10^8. - Michel Marcus, Oct 11 2013

a(6) > 3.3*10^16, if it exists. - Giovanni Resta, Sep 07 2018

Links

Table of n, a(n) for n=1..5.

Example

68^i (i=1..8)= 68, 4624, 314432, 21381376, 1453933568, 98867482624, 6722988818432, 457163239653376 all zeroless.

Mathematica

zLessQ[n_]:=AllTrue[n^Range[8], FreeQ[IntegerDigits[#], 0]&]; Select[Range[70], zLessQ] (* Harvey P. Dale, Sep 27 2023 *)

Prog

(PARI) isok(n) = {for (i = 1, 8, if (! vecmin(digits(n^i)), return (0)); ); return (1); } \\ Michel Marcus, Oct 11 2013

Crossrefs

Cf. A104264.

Sequence in context: A018415 A137073 A018434 * A018448 A018456 A018474

Adjacent sequences: A124646 A124647 A124648 * A124650 A124651 A124652

Keyword

nonn,base,more

Author

Zak Seidov, Dec 22 2006

Status

approved