a=1,1,3,4n=input()y=0exec"y+=1;t='';x=0;%sprint t;"%(n*"a+=a[-2]*4-a[-4],;v=`a[x]`;t+=[v,len(v)*' '][x+y&1];x+=1;")*3
20
1 4 15 56 209 780 2911 10864 40545 151316 1 3 11 41 153 571 2131 7953 29681 110771 1 4 15 56 209 780 2911 10864 40545 151316
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