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
3400
3399
3398
3397
3396
3395
3394
3393
3392
3391
3390
3389
3388
3387
3386
3385
3384
3383
3382
3381
3380