A285455 Least number x such that x^n has n digits equal to k. Case k = 8.

8, 83, 92, 303, 525, 269, 725, 2169, 1298, 3466, 867, 1809, 4624, 793, 7252, 5195, 7521, 21397, 11286, 10482, 19713, 9573, 15815, 27879, 20978, 39673, 53445, 25276, 30943, 93984, 39767, 59441, 92928, 61256, 84303, 113117, 145948, 76304, 109934, 208709, 92674, 189862

Offset

1,1

Links

Table of n, a(n) for n=1..42.

Example

a(4) = 303 because 303^4 = 8428892481 has 4 digits '8' and is the least number to have this property.

Maple

P:=proc(q, h) local a, j, k, n, t; for n from 1 to q do for k from 1 to q do
a:=convert(k^n, base, 10); t:=0; for j from 1 to nops(a) do if a[j]=h then t:=t+1; fi; od;
if t=n then print(k); break; fi; od; od; end: P(10^9, 8);

Mathematica

lnx[n_]:=Module[{x=1}, While[DigitCount[x^n, 10, 8]!=n, x++]; x]; Array[lnx, 50] (* Harvey P. Dale, Jul 05 2023 *)

Crossrefs

Sequence in context: A163191 A241708 A317119 * A068173 A069635 A069620

Adjacent sequences: A285452 A285453 A285454 * A285456 A285457 A285458

Keyword

nonn,base,easy

Author

Paolo P. Lava, Apr 19 2017

Status

approved