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
3380
3379
3378
3377
3376
3375
3374
3373
3372
3371
3370
3369
3368
3367
3366
3365
3364
3363
3362
3361
3360