OFFSET
0,8
COMMENTS
a(n)=1 for 18 values of n = sqrt(A068802);
for n<=1000, a(n)=0 for 22 values of n:
304,353,364,403,407,442,443,463,508,514,589,593,629,634,661,704,736,737,778, 805,807,818.
a(304)=0 because 304^2=92416 and no square can avoid one of digits 1,2,4,6,9:
each square ends with digits 1,4,5,6, or 9 (end zero doesn't matter), and if square ends with 5, then previous digit is 2;
also, a(353)=0 because 353^2=124609 and no square can avoid one of the same digits 1,2,4,6,9.
EXAMPLE
a(0)=1 because squares 0^2=0 and (0+1)^2=1 have no common digits, a(9)=6 because squares 9^2=81 and (9+6)^2=225 have no common digits.
MATHEMATICA
lpk[n_]:=Module[{k=1}, While[ContainsAny[IntegerDigits[n^2], IntegerDigits[ (n+k)^2]], k++]; k]Array[lpk, 100, 0] (* Harvey P. Dale, Jun 17 2016 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Zak Seidov, Feb 20 2009
STATUS
approved