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
12900
12899
12898
12897
12896
12895
12894
12893
12892
12891
12890
12889
12888
12887
12886
12885
12884
12883
12882
12881
12880