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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

No trailing zeros allowed.

LINKS

Zak Seidov, Table of n, a(n) for n = 1..1000

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

Adjacent sequences:  A215615 A215616 A215617 * A215619 A215620 A215621

KEYWORD

nonn,base

AUTHOR

Zak Seidov, Aug 17 2012

STATUS

approved

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Last modified April 15 13:13 EDT 2021. Contains 342977 sequences. (Running on oeis4.)