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
3520
3519
3518
3517
3516
3515
3514
3513
3512
3511
3510
3509
3508
3507
3506
3505
3504
3503
3502
3501
3500