Y \ X
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
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1680
1679
1678
1677
1676
1675
1674
1673
1672
1671
1670
1669
1668
1667
1666
1665
1664
1663
1662
1661
1660