OFFSET
1,2
LINKS
Alois P. Heinz, Table of n, a(n) for n = 1..10000
EXAMPLE
4762 is in the sequence because it is zeroless and 4762^2 = 22676644 has the same set of decimal digits as 4762: {2,4,6,7}.
MAPLE
a:= proc(n) option remember; local k, s;
for k from 1+`if`(n=1, 0, a(n-1)) do
s:= {convert(k, base, 10)[]};
if not 0 in s and s={convert(k^2, base, 10)[]}
then return k fi
od
end:
seq(a(n), n=1..10);
MATHEMATICA
sameQ[n_]:=Union[IntegerDigits[n]]==Union[IntegerDigits[n^2]]; Select[Range@156242, And[FreeQ[IntegerDigits[#], 0], sameQ[#]]&] (* Ivan N. Ianakiev, May 08 2015 *)
PROG
(Python)
A257763_list = [n for n in range(1, 10**6) if not '0' in str(n) and set(str(n)) == set(str(n**2))] # Chai Wah Wu, May 31 2015
(PARI) isok(n) = vecmin(d=digits(n)) && Set(d) == Set(digits(n^2)); \\ Michel Marcus, May 31 2015
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Alois P. Heinz, May 07 2015
STATUS
approved