function y=p(x,s)
if s==1
  y=x^3-3*x^2+6*x-6;
%  y=8*x^3-12*x^2+18*x-15;
elseif s==2
  y=x^5-5*x^4+20*x^3-60*x^2+120*x-120; 
%  y=32*x^5-80*x^4+240*x^3-600*x^2+1050*x-945;
elseif s==3
  y=x^7-7*x^6+42*x^5-210*x^4+840*x^3-2520*x^2+5040*x ...
  -5040;
%  y=128*x^7-448*x^6+2016*x^5-8400*x^4+29400*x^3-79380*x^2 ...
%  +145530*x-135135;
elseif s==4
  y=x^9-9*x^8+72*x^7-504*x^6+3024*x^5-15120*x^4 ...
  +60480*x^3-181440*x^2+362880*x-362880;
%  y=512*x^9-2304*x^8+13824*x^7-80640*x^6+423360*x^5 ...
%  -1905120*x^4+6985440*x^3-19459440*x^2+36486450*x-34459425;
else
  y=x^11-11*x^10+110*x^9-990*x^8+7920*x^7-55440*x^6 ...
  +332640*x^5-1663200*x^4+6652800*x^3-19958400*x^2 ...
  +39916800*x-39916800;
%  y=2048*x^11-11264*x^10+84480*x^9-633600*x^8+4435200*x^7 ...
%  -27941760*x^6+153679680*x^5-713512800*x^4+2675673000*x^3 ...
%  -7581073500*x^2+14404039650*x-13749310575;
end
