Y \ X
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
7700
7699
7698
7697
7696
7695
7694
7693
7692
7691
7690
7689
7688
7687
7686
7685
7684
7683
7682
7681
7680