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%I #6 Mar 31 2012 10:26:02
%S 1,1,1,5,1,3,7,1,1,9,9,3,1,5,11,3,1,5,13,1,13,3,7,1,5,15,3,7,1,17,5,
%T 17,17,1,7,9,5,3,1,7,19,19,5,3,1,7,21,9,21,21,1,11,7,23,5,9,3,1,23,23,
%U 7,5,3,1,25,7,11,25,25,5,13,9,1,7,11,5,3,9,1,27,29,7,11,29,3,1,29,29,7,29,5
%N Values x of smallest positive pair (x,y) satisfying x^2 - 2*y^2 = -+d, where d=A058529(n).
%C Here (x,y) is considered smaller than (u,v) iff x+y < u+v or (x+y = u+v and x < u).
%e A058529(6) = 41; (3, 5), (7, 2), (11, 9), (13, 8), ... are pairs satisfying x^2 - 2*y^2 = -+41; (3, 5) is the smallest one, so a(6) = 3.
%o (PARI) {sp(d)=local(m,b,z,x,y);m=d+2;b=1;z=1;while(b&&z<m,x=1;while(b&&x<z,y=z-x; if(abs(x^2-2*y^2)==d,b=0,x++));if(b,z++));if(b,[ -1,-1,-1],[x,y,z])} {for(n=1,860,fac=factor(n);v=vector(matsize(fac)[1],j,fac[j,1])%8;b=1;for(k=1,length(v),if(v[k]>1&&v[k]<7,b=0));if(b>0,print1(sp(n)[1],",")))}
%Y Cf. A058529, A094137, A094138.
%K nonn
%O 1,4
%A _Lekraj Beedassy_, May 04 2004
%E Edited, corrected and extended by _Klaus Brockhaus_ May 31 2004
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