Doubt in pattern 28

#1 
  1.  1
    2 3 2
    3 4 5 4 3
    4 5 6 7 6 5 4
    5 6 7 8 9 8 7 6 5
    Sir isme val=1 loop ke bhr rkhenge fir jb number print krna hoga toh j loop me val++ krenge yha tk thk h but mirror me kya krenge kuki 13579 aise h virticle me confused ho gyi hu