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
1260
1259
1258
1257
1256
1255
1254
1253
1252
1251
1250
1249
1248
1247
1246
1245
1244
1243
1242
1241
1240