cp's OEIS Frontend

A359343 Square roots of least pandigital squares with n digits.

%I A359343 #15 Jan 05 2023 18:59:39
%S A359343 32043,100287,317096,1000287,3162426,10000287,31622792,100000287,
%T A359343 316227814,1000000287,3162277718,10000000287,31622776661,100000000287,
%U A359343 316227766026,1000000000287,3162277660177,10000000000287,31622776601685,100000000000287,316227766016843
%N A359343 Square roots of least pandigital squares with n digits.
%C A359343 Pandigital squares are perfect squares containing each digit from 0 to 9 at least once.
%F A359343 a(n) = sqrt(A359342(n)).
%F A359343 If n is odd, a(n) = 10^((n-1)/2) + 287. - _Robert Israel_, Dec 29 2022
%F A359343 a(n) = 10^((n-1)/2) + O(1). - _Charles R Greathouse IV_, Dec 30 2022
%p A359343 f:= proc(n); local k;
%p A359343   for k from ceil(10^((n-1)/2)) do
%p A359343     if convert(convert(k^2,base,10),set) = {$0..9} then return k fi
%p A359343   od
%p A359343 end proc:
%p A359343 map(f, [$10..30]); # _Robert Israel_, Dec 29 2022
%o A359343 (Python)
%o A359343 from math import isqrt
%o A359343 def c(n): return len(set(str(n))) == 10
%o A359343 def a(n): return next((k for k in range(isqrt(10**(n-1))+1, isqrt(10**n-1)+1) if c(k*k)), None)
%o A359343 print([a(n) for n in range(10, 31)]) # _Michael S. Branicky_, Dec 27 2022
%Y A359343 Cf. A359342, A359345.
%K A359343 nonn,base
%O A359343 10,1
%A A359343 _Martin Renner_, Dec 27 2022