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
4480
4479
4478
4477
4476
4475
4474
4473
4472
4471
4470
4469
4468
4467
4466
4465
4464
4463
4462
4461
4460