A061659 Numbers k > 1 such that, in base 5, k and k^2 contain the same digits in the same proportion.

9726, 10512, 10904, 12702, 12886, 13766, 13898, 14008, 15086, 37644, 41156, 42006, 42106, 44048, 44448, 44578, 44756, 44826, 48630, 48664, 49482, 49626, 49652, 49676, 51704, 52560, 52582, 54262, 54520, 54982, 57922, 59672, 60778, 63510, 64430, 64736, 65432

Offset: 1

Author

Erich Friedman, Jun 16 2001

Keywords

• base
• easy
• nonn

Examples

			9726 = 302401_5 and 9726^2 = 143204020301_5.
		

Links

• Alois P. Heinz, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A061656, A061657, A061658, A061660, A061661, A061662, A061663, A114258, A061664.

Programs

Maple

p:= n-> add(x^i, i=convert(n, base, 5)):
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