|
%I #9 Sep 27 2023 14:11:35
%S 1,2,3,6,68
%N Numbers n such that n^i (i=1..8) are all zeroless.
%C No other terms < 10^6. Is the sequence finite?
%C Subsequence of A124648. No other terms below 10^8. - _Michel Marcus_, Oct 11 2013
%C a(6) > 3.3*10^16, if it exists. - _Giovanni Resta_, Sep 07 2018
%e 68^i (i=1..8)= 68, 4624, 314432, 21381376, 1453933568, 98867482624, 6722988818432, 457163239653376 all zeroless.
%t zLessQ[n_]:=AllTrue[n^Range[8],FreeQ[IntegerDigits[#],0]&]; Select[Range[70],zLessQ] (* _Harvey P. Dale_, Sep 27 2023 *)
%o (PARI) isok(n) = {for (i = 1, 8, if (! vecmin(digits(n^i)), return (0));); return (1);} \\ _Michel Marcus_, Oct 11 2013
%Y Cf. A104264.
%K nonn,base,more
%O 1,2
%A _Zak Seidov_, Dec 22 2006
|
