lets STUDY

program penjumlahan_angka ganjil;
uses wincrt;
var i,j,n,sum :integer;
begin
readln (n);
begin
if n=1 then write ('1') else
if n>1 then
begin
for i:=n downto 2 do
begin
sum:=1;
j:=(2*i-1);
write (j,'+');
sum:=sum+j;
end;
writeln (1,'=',sum);
end;
end;
end.