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
1750
1749
1748
1747
1746
1745
1744
1743
1742
1741
1740
1739
1738
1737
1736
1735
1734
1733
1732
1731
1730