login
A160109
Numbers k with the property that k^2 uses only nonsquare decimal digits (2,3,5,6,7,8).
1
5, 6, 15, 16, 24, 25, 26, 75, 76, 85, 94, 165, 166, 184, 194, 235, 256, 275, 475, 476, 485, 515, 516, 525, 526, 535, 594, 606, 615, 725, 734, 744, 765, 766, 816, 826, 856, 874, 875, 876, 885, 915, 924, 925, 934, 1524, 1525, 1526, 1535, 1624, 1635, 1665, 1666
OFFSET
1,1
FORMULA
a(n) = sqrt(A077437(n)).
MATHEMATICA
nsdQ[n_]:=Module[{idn=IntegerDigits[n]}, !MemberQ[idn, 1] && And@@SquareFreeQ/@idn]; Select[Range[2000], nsdQ[#^2]&] (* Harvey P. Dale, Feb 01 2011 *)
CROSSREFS
Cf. A077437 (Squares whose decimal digits are nonsquares (2, 3, 5, 6, 7, 8)).
Sequence in context: A282466 A060724 A064949 * A351172 A191213 A121847
KEYWORD
base,nonn
AUTHOR
Zak Seidov, May 02 2009
STATUS
approved