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
3990
3989
3988
3987
3986
3985
3984
3983
3982
3981
3980
3979
3978
3977
3976
3975
3974
3973
3972
3971
3970