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
4950
4949
4948
4947
4946
4945
4944
4943
4942
4941
4940
4939
4938
4937
4936
4935
4934
4933
4932
4931
4930