A285450 Least number x such that x^n has n digits equal to k. Case k = 3.

3, 56, 179, 34, 202, 536, 607, 1182, 1236, 3875, 3076, 2142, 4574, 5378, 9347, 14524, 2013, 8403, 13037, 9534, 20939, 1987, 28882, 27146, 16292, 34546, 48493, 85926, 52953, 48318, 64558, 116514, 49665, 90279, 46911, 117256, 61286, 139083, 120265, 199582, 170357

Offset

1,1

Links

Martin Gossow, Table of n, a(n) for n = 1..100

Example

a(4) = 34 because 34^4 = 1336336 has 4 digits '3' 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, 3);

Prog

(PARI) a(n, k=3) = {my(j=1); while(#select(x->x==k, digits(j^n)) != n, j++); j; } \\ Michel Marcus, Apr 29 2017
(PARI) A285450vec=(n, {k=3})->{my(L:list, c); L=List(); for(t=1, n, forstep(y=1, +oo, 1, c=digits(y^t); if(sum(j=1, #c, c[j]==k)==t, listput(L, y); break()))); return(Vec(L))} \\ Returns a vector containing the first n terms. - R. J. Cano, Apr 29 2017

Crossrefs

Cf. A285448, A285449, A285451, A285452, A285453, A285454, A285455, A285456.

Sequence in context: A290773 A119188 A111451 * A280805 A198184 A262398

Adjacent sequences: A285447 A285448 A285449 * A285451 A285452 A285453

Keyword

nonn,base,easy

Author

Paolo P. Lava, Apr 19 2017

Status

approved