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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.

A364916 Array read by antidiagonals downwards where A(n,k) is the number of ways to write n as a nonnegative linear combination of the parts of a strict integer partition of k.

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%I A364916 #17 Jul 09 2024 19:41:38
%S A364916 1,1,0,1,1,0,2,0,1,0,2,1,1,1,0,3,1,2,0,1,0,4,1,1,3,1,1,0,5,2,2,2,3,0,
%T A364916 1,0,6,2,4,2,3,3,1,1,0,8,3,4,4,3,2,5,0,1,0,10,3,5,4,7,4,3,4,1,1,0,12,
%U A364916 5,6,6,7,7,4,3,5,0,1,0,15,5,9,7,8,6,12,3,4,6,1,1,0
%N A364916 Array read by antidiagonals downwards where A(n,k) is the number of ways to write n as a nonnegative linear combination of the parts of a strict integer partition of k.
%C A364916 A way of writing n as a (nonnegative) linear combination of a finite sequence y is any sequence of pairs (k_i,y_i) such that k_i >= 0 and Sum k_i*y_i = n. For example, the pairs ((3,1),(1,1),(1,1),(0,2)) are a way of writing 5 as a linear combination of (1,1,1,2), namely 5 = 3*1 + 1*1 + 1*1 + 0*2. Of course, there are A000041(n) ways to write n as a linear combination of (1..n).
%C A364916 As a triangle, also the number of ways to write n as a *positive* linear combination of the parts of a strict integer partition of k.
%H A364916 Alois P. Heinz, <a href="/A364916/b364916.txt">Antidiagonals n = 0..200, flattened</a>
%e A364916 Array begins:
%e A364916   1  1  1  2  2  3  4   5   6   8   10   12  15   18   22   27
%e A364916   0  1  0  1  1  1  2   2   3   3   5    5   7    8    10   12
%e A364916   0  1  1  2  1  2  4   4   5   6   9    10  13   15   19   23
%e A364916   0  1  0  3  2  2  4   4   6   7   11   11  15   17   22   27
%e A364916   0  1  1  3  3  3  7   7   8   10  16   17  23   27   33   42
%e A364916   0  1  0  3  2  4  7   6   9   9   17   17  23   26   33   43
%e A364916   0  1  1  5  3  4  12  10  13  16  26   27  36   42   52   68
%e A364916   0  1  0  4  3  3  10  11  13  13  27   25  35   40   51   67
%e A364916   0  1  1  5  4  5  15  13  19  20  36   37  51   58   72   97
%e A364916   0  1  0  6  4  5  14  13  18  23  42   39  54   61   78   105
%e A364916   0  1  1  6  4  6  20  17  23  25  54   50  69   80   98   138
%e A364916   0  1  0  6  4  5  19  16  23  24  54   55  71   80   103  144
%e A364916   0  1  1  8  6  7  27  23  30  35  72   70  103  113  139  199
%e A364916   0  1  0  7  5  6  24  21  29  31  75   68  95   115  139  201
%e A364916   0  1  1  8  5  7  31  27  36  39  90   86  122  137  178  255
%e A364916   0  1  0  9  6  8  31  27  38  42  100  93  129  148  187  289
%e A364916 Triangle begins:
%e A364916    1
%e A364916    1  0
%e A364916    1  1  0
%e A364916    2  0  1  0
%e A364916    2  1  1  1  0
%e A364916    3  1  2  0  1  0
%e A364916    4  1  1  3  1  1  0
%e A364916    5  2  2  2  3  0  1  0
%e A364916    6  2  4  2  3  3  1  1  0
%e A364916    8  3  4  4  3  2  5  0  1  0
%e A364916   10  3  5  4  7  4  3  4  1  1  0
%e A364916   12  5  6  6  7  7  4  3  5  0  1  0
%e A364916   15  5  9  7  8  6 12  3  4  6  1  1  0
%e A364916   18  7 10 11 10  9 10 10  5  4  6  0  1  0
%e A364916   22  8 13 11 16  9 13 11 15  5  4  6  1  1  0
%e A364916   27 10 15 15 17 17 16 13 13 14  6  4  8  0  1  0
%t A364916 combs[n_,y_]:=With[{s=Table[{k,i},{k,y},{i,0,Floor[n/k]}]},Select[Tuples[s],Total[Times@@@#]==n&]];
%t A364916 t[n_,k_]:=Length[Join@@Table[combs[n,ptn],{ptn,Select[IntegerPartitions[k],UnsameQ@@#&]}]];
%t A364916 Table[t[k,n-k],{n,0,15},{k,0,n}]
%Y A364916 Same as A116861 with offset 0 and rows reversed, non-strict version A364912.
%Y A364916 Row n = 0 is A000009.
%Y A364916 Row n = 1 is A096765.
%Y A364916 Row n = 2 is A365005.
%Y A364916 Column k = 0 is A000007.
%Y A364916 Column k = 1 is A000012.
%Y A364916 Column k = 2 is A000035.
%Y A364916 Column k = 3 is A137719.
%Y A364916 The main diagonal is A364910.
%Y A364916 Left half has row sums A365002.
%Y A364916 For not just strict partitions we have A365004, diagonal A364907.
%Y A364916 A000041 counts integer partitions, strict A000009.
%Y A364916 A008284 counts partitions by length, strict A008289.
%Y A364916 A066328 adds up distinct prime indices.
%Y A364916 A364350 counts combination-free strict partitions, complement A364839.
%Y A364916 Cf. A007865, A085489, A108917, A237113, A323092, A364272, A364533, A364670, A364911, A364913.
%K A364916 nonn,tabl
%O A364916 0,7
%A A364916 _Gus Wiseman_, Aug 17 2023