import Data.List
import Control.Monad

yoba n = foldM (\r x -> putStrLn (
			if odd r then "" else "  " ++ replicate (r `div` 2) '\t' ++ intercalate "\t" (map show x)
		 ) >> return (r - 1)) n
	$ take n $ iterate (\row -> zipWith (+) ([0] ++ row) (row ++ [0])) [1]

main = yoba 15