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A215618
Sum of digits of n^2 is a square.
1
1, 2, 3, 6, 9, 11, 12, 13, 14, 15, 18, 21, 22, 23, 31, 39, 41, 45, 48, 51, 58, 59, 67, 68, 76, 77, 85, 86, 94, 95, 101, 102, 103, 104, 105, 111, 112, 113, 121, 122, 131, 139, 148, 157, 158, 166, 175, 176, 184, 185, 193, 194, 201, 202, 203, 211, 212, 221, 229
OFFSET
1,2
COMMENTS
No trailing zeros allowed.
EXAMPLE
a(59)=229 because 229^2=52441 and 5+2+4+4+1=16=4^2.
MATHEMATICA
sdn2Q[n_]:=Module[{idn2=IntegerDigits[n^2]}, Last[idn2]>0&&IntegerQ[Sqrt[ Total[idn2]]]]; Select[Range[300], sdn2Q] (* Harvey P. Dale, Aug 27 2013 *)
CROSSREFS
Cf. A004159 (sum of digits of n^2).
Sequence in context: A015898 A157217 A058958 * A189708 A127590 A118730
KEYWORD
nonn,base
AUTHOR
Zak Seidov, Aug 17 2012
STATUS
approved