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 A233821 Smallest zeroless number x such that x^n has exactly n zero digits. 1
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,1 LINKS EXAMPLE 951 has no zeros and 951^10 has ten zeros (605069371210073000039238122001). This is the least positive integer with this property. MAPLE 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: seq(A[n], n=2..N); # Robert Israel, Aug 05 2014 PROG (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 CROSSREFS Cf. A052382. Sequence in context: A291587 A220090 A013684 * A216233 A157246 A186460 Adjacent sequences:  A233818 A233819 A233820 * A233822 A233823 A233824 KEYWORD nonn,base AUTHOR Derek Orr, Dec 16 2013 EXTENSIONS More terms from Michel Marcus, Dec 23 2013 Definition edited by Robert Israel, Aug 05 2014 Definition simplified by Derek Orr, Mar 23 2015 STATUS approved

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Last modified December 13 01:23 EST 2019. Contains 329963 sequences. (Running on oeis4.)