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A061658
Numbers k > 1 such that, in base 4, k and k^2 contain the same digits in the same proportion.
12
45, 165, 180, 657, 660, 720, 882, 2165, 2193, 2331, 2625, 2628, 2640, 2880, 3362, 3470, 3528, 3606, 3683, 3825, 8285, 8294, 8337, 8381, 8477, 8493, 8519, 8525, 8660, 8721, 8772, 8817, 9069, 9282, 9324, 9479, 9507, 9869, 9969, 10185, 10349, 10353, 10500, 10512
OFFSET
1,1
LINKS
EXAMPLE
45 = 231_4 and 45^2 = 133221_4.
MAPLE
p:= n-> add(x^i, i=convert(n, base, 4)):
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
KEYWORD
base,easy,nonn
AUTHOR
Erich Friedman, Jun 16 2001
EXTENSIONS
Offset changed to 1 by Alois P. Heinz, May 10 2015
STATUS
approved