A135857 Partial sums triangle based on A016777. Riordan convolution triangle ((1 + 2*x)/(1-x)^2, x/(1-x)).
1, 4, 1, 7, 5, 1, 10, 12, 6, 1, 13, 22, 18, 7, 1, 16, 35, 40, 25, 8, 1, 19, 51, 75, 65, 33, 9, 1, 22, 70, 126, 140, 98, 42, 10, 1, 25, 92, 196, 266, 238, 140, 52, 11, 1, 28, 117, 288, 462, 504, 378, 192, 63, 12, 1
Offset: 0
Examples
The triangle T(n, k) begins: n\k 0 1 2 3 4 5 6 7 8 9 10 11 0: 1 1: 4 1 2: 7 5 1 3: 10 12 6 1 4: 13 22 18 7 1 5: 16 35 40 25 8 1 6: 19 51 75 65 33 9 1 7: 22 70 126 140 98 42 10 1 8: 25 92 196 266 238 140 52 11 1 9: 28 117 288 462 504 378 192 63 12 1 10: 31 145 405 750 966 882 570 255 75 13 1 11: 34 176 550 1155 1716 1848 1452 825 330 88 14 1 ... reformatted and extended by _Wolfdieter Lang_, Mar 23 2015 From _Wolfdieter Lang_, Mar 23 2015: (Start) T(3, 1) = T(2, 0) + T(2, 1) = 7 + 5 = 12 (Pascal, from the A-sequence given above). T(4, 0) = 4*T(3, 0) - 9*T(3, 1) + 27*T(3, 2) - 81* T(3, 3) = 4*10 - 9*12 + 27*6 - 81*1 = 13, from the Z-sequence given above and in A256096. T(4, 0) = 2*T(3, 0) - T(2, 0) = 2*10 - 7 = 13. (End)
Crossrefs
Formula
Binomial transform of an infinite lower triangular matrix with all 1's in the main diagonal and all 3's in the subdiagonal; i.e., by columns - every column = (1, 3, 0, 0, 0, ...).
T(n,k) = (3n-2k+1)*binomial(n+1,k+1)/(n+1). - Philippe Deléham, Feb 08 2009
From Wolfdieter Lang, Mar 23 2015: (Start)
O.g.f. for row polynomials: (1 + 2*z)/((1- z*(1 + x))*(1 - z)) (see the Riordan property from the comment).
O.g.f. for column k (without leading zeros): (1 + 2*x)/(1-x)^(2+k), k >= 0, (Riordan property).
T(n, k) = T(n-1, k-1) + T(n-1, k) for k >= 1. From the Riordan A-sequence given above in a comment.
T(n, 0) = Sum_{j=0..n} Z(j)*T(n-1, j), for n >= 1, from the Riordan Z-sequence A256096 mentioned above in a comment. Of course, T(n, 0) = 2*T(n-1, 0) - T(n-2, 0) for n >= 2 (see A016777).
(End)
Extensions
Edited. Offset is 0 from the old name and the Philippe Deléham formula. New name, old name as first comment. - Wolfdieter Lang, Mar 23 2015
Comments