Y \ X
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
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
1580
1579
1578
1577
1576
1575
1574
1573
1572
1571
1570
1569
1568
1567
1566
1565
1564
1563
1562
1561
1560