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Triangle by rows, generated from the odd integers and related to A000165.
3

%I #21 Mar 09 2015 06:07:22

%S 1,1,1,4,3,1,24,18,5,1,192,144,40,7,1,1920,1440,400,70,9,1,23040,

%T 17280,4800,840,108,11,1,322560,241920,67200,11760,1512,154,13,1,

%U 5160960,3870720,1075200,188160,24192,2464,208,15,1

%N Triangle by rows, generated from the odd integers and related to A000165.

%C Row sums = A000165, the double factorial numbers: (1, 2, 8, 48, 384,...).

%C Left border = A002866 and the eigensequence of the odd integers prefaced with a 1.

%H Alois P. Heinz, <a href="/A208057/b208057.txt">Rows n = 0..140, flattened</a>

%F Eigentriangle of triangle A158405 (odd integers in every row: (1, 3, 5,...); the inverse of:

%F 1;

%F -1, 1;

%F -1, -3, 1;

%F -1, -3, -5, 1;

%F -1, -3, -5, -7, 1;

%F ...

%e First few rows of the triangle =

%e 1;

%e 1, 1;

%e 4, 3, 1;

%e 24, 18, 5, 1;

%e 192, 144, 40, 7, 1;

%e 1920, 1440, 400, 70, 9, 1;

%e 23040, 17280, 4800, 840, 108, 11, 1;

%e 322560, 241920, 67200, 11760, 1512, 154, 13, 1;

%e ...

%p T:= proc(n) option remember; local M;

%p M:= (Matrix(n+1, (i, j)-> `if`(i=j, 1, `if`(i>j, -2*j+1, 0)))^(-1));

%p seq(M[n+1, k], k=1..n+1)

%p end:

%p seq(T(n), n=0..10); # _Alois P. Heinz_, Feb 27 2012

%t T[n_] := T[n] = Module[{M}, M = Table[If[i == j, 1, If[i>j, -2*j+1, 0]], {i, 1, n+1 }, {j, 1, n+1}] // Inverse; M[[n+1]]]; Table[T[n], {n, 0, 10}] // Flatten (* _Jean-François Alcover_, Mar 09 2015, after _Alois P. Heinz_ *)

%Y Cf. A000165, A002866, A158405.

%K nonn,tabl

%O 0,4

%A _Gary W. Adamson_, Feb 22 2012

%E Typo in term 17 corrected by _Alois P. Heinz_, Dec 06 2012