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
6640
6639
6638
6637
6636
6635
6634
6633
6632
6631
6630
6629
6628
6627
6626
6625
6624
6623
6622
6621
6620