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
4580
4579
4578
4577
4576
4575
4574
4573
4572
4571
4570
4569
4568
4567
4566
4565
4564
4563
4562
4561
4560