a(n,m) tabl head (triangle) for A035469 S2(4) n\m 1 2 3 4 5 6 7 8 9 10 1 1 0 0 0 0 0 0 0 0 0 2 4 1 0 0 0 0 0 0 0 0 3 28 12 1 0 0 0 0 0 0 0 4 280 160 24 1 0 0 0 0 0 0 5 3640 2520 520 40 1 0 0 0 0 0 6 58240 46480 11880 1280 60 1 0 0 0 0 7 1106560 987840 295960 40040 2660 84 1 0 0 0 8 24344320 23826880 8090880 1296960 109200 4928 112 1 0 0 9 608608000 643843200 242280640 44405760 4463760 257040 8400 144 1 0 10 17041024000 19280060800 7912262400 1618859200 187246080 12946080 542640 13440 180 1 etc.