OFFSET
1,1
COMMENTS
floor(sqrt(2)*10^(n-1)) < a(n). - Robert G. Wilson v, Oct 04 2005
MATHEMATICA
f[n_] := Block[{k = Ceiling[10^n*(1/9 + .03032)]}, While[ Intersection[ IntegerDigits[k], IntegerDigits[k^2]] != {}, k++ ]; k]; Table[ f[n], {n, 18}] (* Robert G. Wilson v *)
PROG
(Python)
from math import isqrt
def a(n):
m = isqrt(int('2'+'0'*(2*n-2)))
while set(str(m*m)) & set(str(m)) != set(): m += 1
return m
print([a(n) for n in range(1, 12)]) # Michael S. Branicky, Feb 17 2021
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Lekraj Beedassy, Aug 17 2005
EXTENSIONS
a(3) to a(6) corrected, a(7) to a(13) from Klaus Brockhaus, Aug 31 2005; revised Sep 09 2005
a(14)-a(18) from Robert G. Wilson v, Oct 04 2005
STATUS
approved