O15-C919
> restart:
> coe:=proc(l,n)
> local res,k;
> res:=array(0..n);
> res[0]:=1;res[1]:=-l/6;
> for k from 2 to n do res[k]:=-(l*res[k-1]+res[k-2])/2/k/(2*k+1) od;
> res;end;

> c:=coe(l,2):0,seq(op([c[k],0]),k=0..2);

                                       2
                                      l
                   0, 1, 0, - l/6, 0, --- - 1/20, 0
                                      120

> ed:=l->diff(y(x),x$2)+(l+x^2)*y(x);

> s:=[seq(subs(dsolve({ed(l),y(0)=0,D(y)(0)=1},y(x)),y(x)),l=-2..2)];

> a:=[seq(subs(l=j,sum(c[k]*x^(2*k+1),k=0..2)),j=-2..2)];

                 3         5           3         5            5
  a := [x + 1/3 x  - 1/60 x , x + 1/6 x  - 1/24 x , x - 1/20 x ,

                 3         5           3         5
        x - 1/6 x  - 1/24 x , x - 1/3 x  - 1/60 x ]

> h:=k->plot([s[k],a[k]],x=0..2);

> for k from 1 to 5 do h(k) od:
>