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 A106602 Number of primitive positive solutions to 8n+2=x^2+y^2. 2
 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 0, 1, 2, 0, 1, 0, 0, 2, 1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 2, 1, 0, 1, 0, 0, 1, 1, 0, 1, 2, 0, 1, 1, 0, 2, 0, 0, 0, 2, 0, 1, 1, 0, 1, 0, 0, 0, 1, 0, 2, 1, 0, 1, 1, 0, 1, 1, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,17 LINKS R. J. Mathar, Table of n, a(n) for n = 0..1000 EXAMPLE a(16)=2 because we have 130=11^2+3^2=9^2+7^2. a(2)=0 because although 18=3^2+3^2, these components are not mutually prime. MAPLE A106602 := proc(n)     local a, x, y, fourn;     fourn := 8*n+2 ;     a := 0 ;     for x from 1 do         if x^2 >= fourn then             return a;         else             y := fourn-x^2 ;             if issqr(y) then                 y := sqrt(y) ;                 if y <= x and igcd(x, y) = 1 then                     a := a+1 ;                 end if;             end if;         end if:     end do: end proc: # R. J. Mathar, Sep 21 2013 CROSSREFS Cf. A106594. Sequence in context: A104451 A285680 A240668 * A106594 A143251 A115235 Adjacent sequences:  A106599 A106600 A106601 * A106603 A106604 A106605 KEYWORD easy,nonn AUTHOR Colin Mallows, May 10 2005 STATUS approved

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Last modified February 28 11:08 EST 2020. Contains 332323 sequences. (Running on oeis4.)