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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.

A128627 Triangle read by rows. Convolution triangle based on A002865.

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%I A128627 #12 Oct 03 2022 08:46:46
%S A128627 1,0,1,1,0,1,1,2,0,1,2,2,3,0,1,2,5,3,4,0,1,4,6,9,4,5,0,1,4,13,12,14,5,
%T A128627 6,0,1,7,16,28,20,20,6,7,0,1,8,30,39,50,30,27,7,8,0,1,12,40,78,76,80,
%U A128627 42,35,8,9,0,1,14,66,115,161,130,119,56,44,9,10,0,1
%N A128627 Triangle read by rows. Convolution triangle based on A002865.
%C A128627 Triangular array illustrating the application of cyclic partitions to the computation of partitions of an integer into parts of k kinds (cf. A060850).
%C A128627 The array is constructed by summing sequences associated with each cyclic partition as indicated below: (n' here denotes the sum of preceding sequences).
%C A128627   4      1     2     3
%C A128627   22     1     3     6
%C A128627   4'     2     5     9
%C A128627   5      1     2     3     4
%C A128627   32     1     4     9    16
%C A128627   5'     2     6    12    20
%C A128627   6      1     2     3     4     5     6     7     8     9
%C A128627   42     1     4     9    16    25    36    49    64    81
%C A128627   33     1     3     6    10    15    21    28    36    45
%C A128627   222    1     4    10    20    35    56    84   120   165
%C A128627   6'     4    13    28    50    80   119   168   228   300
%C A128627   7      1     2     3     4     5     6     7     8     9
%C A128627   52     1     4     9    16    25    36    49    64    81
%C A128627   43     1     4     9    16    25    36    49    64    81
%C A128627   322    1     6    18    40    75   126   196   288   405
%C A128627   7'     4    16    39    76   130   204   301   424   576
%C A128627   8      1     2     3     4     5     6     7     8     9
%C A128627   62     1     4     9    16    25    36    49    64    81
%C A128627   53     1     4     9    16    25    36    49    64    81
%C A128627   44     1     3     6    10    15    21    28    36    45
%C A128627   422    1     6    18    40    75   126   196   288   405
%C A128627   332    1     6    18    40    75   126   196   288   405
%C A128627   2222   1     5    15    35    70   126   210   330   495
%C A128627   8'     7    30    78   161   290   477   735  1078  1521
%e A128627 The diagonal 9th diagonal of A060850 is 22 185 810 2580 6765 ... and can be computed from a(n) and A007318 as illustrated:
%e A128627    1
%e A128627    0    1
%e A128627    1    0    1
%e A128627    1    2    0    1
%e A128627    2    2    3    0
%e A128627    2    5    3    4
%e A128627    4    6    9    4
%e A128627    4   13   12   14
%e A128627    7   16   28   20
%e A128627        30   39   50
%e A128627             78   76
%e A128627                 161
%e A128627 times
%e A128627    1
%e A128627    1    9
%e A128627    1    8   45
%e A128627    1    7   36  165
%e A128627    1    6   28  120
%e A128627    1    5   21   84
%e A128627    1    4   15   56
%e A128627    1    3   10   35
%e A128627    1    2    6   20
%e A128627         1    3   10
%e A128627              1    4
%e A128627                   1
%e A128627 yields
%e A128627    1
%e A128627    0    9
%e A128627    1    0   45
%e A128627    1   14    0  165
%e A128627    2   12   84    0
%e A128627    2   25   63  336
%e A128627    4   24  135  224
%e A128627    4   39  120  490
%e A128627    7   32  168  400
%e A128627        30  117  500
%e A128627             78  304
%e A128627                 161
%e A128627 summing to
%e A128627   22  185  810 2580 ...
%e A128627 Triangle T(n, k) starts:
%e A128627   [ 1] 1;
%e A128627   [ 2] 0,  1;
%e A128627   [ 3] 1,  0,  1;
%e A128627   [ 4] 1,  2,  0,  1;
%e A128627   [ 5] 2,  2,  3,  0,  1;
%e A128627   [ 6] 2,  5,  3,  4,  0,  1;
%e A128627   [ 7] 4,  6,  9,  4,  5,  0,  1;
%e A128627   [ 8] 4, 13, 12, 14,  5,  6,  0,  1;
%e A128627   [ 9] 7, 16, 28, 20, 20,  6,  7,  0,  1;
%e A128627   [10] 8, 30, 39, 50, 30, 27,  7,  8,  0,  1;
%p A128627 # Using function A002865 and function PMatrix from A357368.
%p A128627 A128627Triangle := proc(dim) local M, Row, r;
%p A128627 M := PMatrix(dim, n -> A002865(n-1));
%p A128627 Row := r -> convert(linalg:-row(M, r), list)[2..r];
%p A128627 for r from 2 to dim do lprint(Row(r)) od end:
%p A128627 A128627Triangle(11); # _Peter Luschny_, Oct 03 2022
%Y A128627 Cf. A002865, A060850, A007318.
%K A128627 nonn,tabl
%O A128627 1,8
%A A128627 _Alford Arnold_, Mar 22 2007
%E A128627 New name by _Peter Luschny_, Oct 03 2022