Y \ X
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
5000
4999
4998
4997
4996
4995
4994
4993
4992
4991
4990
4989
4988
4987
4986
4985
4984
4983
4982
4981
4980