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
13920
13919
13918
13917
13916
13915
13914
13913
13912
13911
13910
13909
13908
13907
13906
13905
13904
13903
13902
13901
13900