Y \ X
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
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
6900
6899
6898
6897
6896
6895
6894
6893
6892
6891
6890
6889
6888
6887
6886
6885
6884
6883
6882
6881
6880