Y \ X
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
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
4950
4949
4948
4947
4946
4945
4944
4943
4942
4941
4940
4939
4938
4937
4936
4935
4934
4933
4932
4931
4930