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
4400
4399
4398
4397
4396
4395
4394
4393
4392
4391
4390
4389
4388
4387
4386
4385
4384
4383
4382
4381
4380