A061657 Numbers k > 1 such that, in base 3, k and k^2 contain the same digits in the same proportion.

184, 196, 464, 500, 544, 550, 552, 584, 588, 622, 626, 670, 706, 1392, 1436, 1472, 1500, 1552, 1632, 1650, 1654, 1656, 1744, 1752, 1764, 1866, 1868, 1878, 1978, 2010, 2030, 2116, 2118, 3922, 4136, 4176, 4308, 4388, 4416, 4500, 4656, 4732, 4756, 4896, 4900

Offset: 1

Author

Erich Friedman, Jun 16 2001

Keywords

• base
• easy
• nonn

Examples

			184 = 20211_3 and 184^2 = 1201102221_3.
		

Links

• Alois P. Heinz, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A061656, A061658, A061659, A061660, A061661, A061662, A061663, A114258, A061664.

Programs

Maple

p:= n-> add(x^i, i=convert(n, base, 3)):
a:= proc(n) option remember; local k;
      for k from 1+`if`(n=1, 0, a(n-1))
      while p(k)*2<>p(k^2) do od; k
    end:
seq(a(n), n=1..50);  # Alois P. Heinz, May 10 2015

Extensions

Offset changed to 1 by Alois P. Heinz, May 10 2015