This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A181417 #8 Feb 12 2013 15:38:58 %S A181417 1,1,2,1,12,6,1,24,18,108,24,1,40,80,360,540,960,120,1,60,150,100,900, %T A181417 3600,900,4800,10800,9000,720,1,84,252,420,1890,9450,6300,9450,16800, %U A181417 100800,50400,63000,189000,90720,5040,1,112,392,784,490,3528,21168,35280,26460,35280,47040,352800,235200,705600,88200,294000,2352000,1764000,846720,3175200,987840,40320,1,144,576,1344,2016,6048,42336 %N A181417 Irregular triangle T(n,k) = binomial(n-1,m-1)*m!*A036040(n,k), where m=A036043(n,k). %C A181417 This is a refinement of the triangle A048743. %C A181417 Row n has A000041(n) elements. %C A181417 The sequence can be derived by expanding A007318 and A000142 and using A036040. %C A181417 For example, row four can be derived using %C A181417 (1 3 3 3 1) times (1 2 2 6 24) times (1 4 3 6 1) = (1 24 18 108 24) %e A181417 The table begins: %e A181417 1 %e A181417 1...2 %e A181417 1..12...6 %e A181417 1..24..18..108..24 %Y A181417 Cf. A045531 (row sums), A048743, A007318, A036040. %K A181417 nonn,tabf %O A181417 1,3 %A A181417 _Alford Arnold_, Oct 22 2010 %E A181417 Row 6 onwards and definition by _R. J. Mathar_, Feb 12 2013