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A233821
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Smallest zeroless number x such that x^n has exactly n zero digits.
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1
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245, 126, 245, 321, 351, 1244, 194, 4648, 951, 4357, 3757, 2169, 2392, 7399, 8379, 9723, 8683, 13867, 6152, 24887, 18898, 55825, 54631, 29647, 35586, 46564, 67743, 84789, 119421, 72296, 43642, 92233, 44411, 142553, 126693, 135852, 52299, 229626, 143951
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OFFSET
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2,1
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LINKS
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EXAMPLE
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951 has no zeros and 951^10 has ten zeros (605069371210073000039238122001). This is the least positive integer with this property.
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MAPLE
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N:= 30: # to get terms up to a(N)
for n from 2 to N do
for k from 1 do
if numboccur(0, convert(k, base, 10)) = 0 and
numboccur(0, convert(k^n, base, 10)) = n then
A[n]:= k;
break
fi
od
od:
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PROG
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(Python)
def GetNums(x):
..for n in range(10**6):
....if str(n).count("0") == 0:
......if str(n**x).count("0") == x:
........return n
x = 2
while x < 50:
..print(GetNums(x), end=', ')
..x += 1
(PARI) okxn(x, n) = {ok = 0; if (vecmin (digits(x)), dxn = digits(x^n); ok = (sum(i=1, #dxn, dxn[i] == 0) == n); ); ok; }
a(n) = {x=1; while (! okxn(x, n), x++); x; } \\ Michel Marcus, Dec 23 2013
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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Definition simplified by Derek Orr, Mar 23 2015
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STATUS
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approved
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