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A024804 Numbers that are the sum of 3 distinct nonzero squares in 2 or more ways. 3
62, 69, 74, 77, 86, 89, 90, 94, 98, 101, 105, 110, 117, 122, 125, 126, 129, 131, 134, 138, 141, 146, 149, 150, 154, 155, 158, 161, 165, 166, 170, 173, 174, 179, 181, 182, 185, 186, 189, 194, 195, 197, 201, 203, 206, 209, 210, 213, 217, 218, 221, 222, 225, 227, 229, 230 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..56.

Index entries for sequences related to sums of squares

FORMULA

{n: A025442(n) >= 2}.

MAPLE

isA024804 := proc(n) local ws; ws := 0 ; for x from 1 do if x^2 > n then break; end if; for y from x+1 do if x^2+y^2>n then break; end if; z := n-x^2-y^2 ; if issqr(z) then z := sqrt(z) ; if z > y then ws := ws+1 ; end if; end if ; end do: end do: ws >= 2 ; end proc:

for n from 1 to 230 do if isA024804(n) then printf("%d, ", n) ; end if; end do: # R. J. Mathar, Dec 07 2010

MATHEMATICA

nn=230; t=Table[0, {nn}]; Do[n=i^2+j^2+k^2; If[n<=nn, t[[n]]++], {i, Sqrt[nn]}, {j, i+1, Sqrt[nn]}, {k, j+1, Sqrt[nn]}]; Flatten[Position[t, _?(#>1&)]]

CROSSREFS

Sequence in context: A095577 A095565 A095553 * A025340 A048127 A047823

Adjacent sequences:  A024801 A024802 A024803 * A024805 A024806 A024807

KEYWORD

nonn

AUTHOR

Clark Kimberling

STATUS

approved

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Last modified June 23 16:45 EDT 2017. Contains 288666 sequences.