# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a356013 Showing 1-1 of 1 %I A356013 #12 Jul 23 2022 09:54:12 %S A356013 1,1,1,2,3,1,6,6,4,1,24,30,20,5,1,120,120,60,30,6,1,720,840,420,210, %T A356013 42,7,1,5040,5040,3360,840,336,56,8,1,40320,45360,20160,7560,3024,504, %U A356013 72,9,1,362880,362880,201600,75600,15120,5040,720,90,10,1 %N A356013 Triangle T(n,k), n >= 1, 1 <= k <= n, read by rows, where T(n,k) = n!/(k! * floor(n/k)). %F A356013 E.g.f. of column k: -(1 - x^k) * log(1 - x^k)/(k! * (1 - x)). %e A356013 Triangle begins: %e A356013 1; %e A356013 1, 1; %e A356013 2, 3, 1; %e A356013 6, 6, 4, 1; %e A356013 24, 30, 20, 5, 1; %e A356013 120, 120, 60, 30, 6, 1; %e A356013 720, 840, 420, 210, 42, 7, 1; %e A356013 5040, 5040, 3360, 840, 336, 56, 8, 1; %e A356013 40320, 45360, 20160, 7560, 3024, 504, 72, 9, 1; %e A356013 ... %o A356013 (PARI) T(n, k) = n!/(k!*(n\k)); %Y A356013 Row sums gives A356011. %Y A356013 Column k=1..3 give A000142(n-1), |A265376(n)|, A356012. %Y A356013 Cf. A355996. %K A356013 nonn,tabl %O A356013 1,4 %A A356013 _Seiichi Manyama_, Jul 23 2022 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE