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 A181417 Irregular triangle T(n,k) = binomial(n-1,m-1)*m!*A036040(n,k), where m=A036043(n,k). 0
 1, 1, 2, 1, 12, 6, 1, 24, 18, 108, 24, 1, 40, 80, 360, 540, 960, 120, 1, 60, 150, 100, 900, 3600, 900, 4800, 10800, 9000, 720, 1, 84, 252, 420, 1890, 9450, 6300, 9450, 16800, 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS This is a refinement of the triangle A048743. Row n has A000041(n) elements. The sequence can be derived by expanding A007318 and A000142 and using A036040. For example, row four can be derived using (1 3 3 3 1) times (1 2 2 6 24) times (1 4 3 6 1) = (1 24 18 108 24) LINKS EXAMPLE The table begins: 1 1...2 1..12...6 1..24..18..108..24 CROSSREFS Cf. A045531 (row sums), A048743, A007318, A036040. Sequence in context: A288359 A107722 A167128 * A048743 A049055 A276998 Adjacent sequences:  A181414 A181415 A181416 * A181418 A181419 A181420 KEYWORD nonn,tabf AUTHOR Alford Arnold, Oct 22 2010 EXTENSIONS Row 6 onwards and definition by R. J. Mathar, Feb 12 2013 STATUS approved

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Last modified July 23 14:24 EDT 2019. Contains 325254 sequences. (Running on oeis4.)