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
3750
3749
3748
3747
3746
3745
3744
3743
3742
3741
3740
3739
3738
3737
3736
3735
3734
3733
3732
3731
3730