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
4100
4099
4098
4097
4096
4095
4094
4093
4092
4091
4090
4089
4088
4087
4086
4085
4084
4083
4082
4081
4080