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%I #28 Mar 26 2015 13:59:13
%S 245,126,245,321,351,1244,194,4648,951,4357,3757,2169,2392,7399,8379,
%T 9723,8683,13867,6152,24887,18898,55825,54631,29647,35586,46564,67743,
%U 84789,119421,72296,43642,92233,44411,142553,126693,135852,52299,229626,143951
%N Smallest zeroless number x such that x^n has exactly n zero digits.
%e 951 has no zeros and 951^10 has ten zeros (605069371210073000039238122001). This is the least positive integer with this property.
%p N:= 30: # to get terms up to a(N)
%p for n from 2 to N do
%p for k from 1 do
%p if numboccur(0,convert(k,base,10)) = 0 and
%p numboccur(0,convert(k^n, base, 10)) = n then
%p A[n]:= k;
%p break
%p fi
%p od
%p od:
%p seq(A[n],n=2..N); # _Robert Israel_, Aug 05 2014
%o (Python)
%o def GetNums(x):
%o ..for n in range(10**6):
%o ....if str(n).count("0") == 0:
%o ......if str(n**x).count("0") == x:
%o ........return n
%o x = 2
%o while x < 50:
%o ..print(GetNums(x),end=', ')
%o ..x += 1
%o (PARI) okxn(x, n) = {ok = 0; if (vecmin (digits(x)), dxn = digits(x^n); ok = (sum(i=1, #dxn, dxn[i] == 0) == n);); ok;}
%o a(n) = {x=1; while (! okxn(x, n), x++); x;} \\ _Michel Marcus_, Dec 23 2013
%Y Cf. A052382.
%K nonn,base
%O 2,1
%A _Derek Orr_, Dec 16 2013
%E More terms from _Michel Marcus_, Dec 23 2013
%E Definition edited by _Robert Israel_, Aug 05 2014
%E Definition simplified by _Derek Orr_, Mar 23 2015
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