cp's OEIS Frontend

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.

A365383 Triangle read by rows where T(n,k) is the number of integer partitions of n that can be linearly combined with nonnegative coefficients to obtain k.

This page as a plain text file.
%I A365383 #6 Sep 09 2023 06:55:49
%S A365383 1,2,1,3,2,2,5,3,4,3,7,5,6,6,6,11,7,9,8,9,7,15,11,13,13,14,13,14,22,
%T A365383 15,19,17,20,17,20,16,30,22,26,26,27,26,28,26,27,42,30,37,34,39,33,40,
%U A365383 34,39,34,56,42,50,49,52,50,54,51,54,53,53
%N A365383 Triangle read by rows where T(n,k) is the number of integer partitions of n that can be linearly combined with nonnegative coefficients to obtain k.
%C A365383 Conjecture: The rows eventually become periodic with period n if extended further. For example, row n = 8 begins:
%C A365383   22, 15, 19, 17, 20, 17, 20, 16,
%C A365383   22, 17, 20, 17, 21, 17, 20, 17,
%C A365383   22, 17, 20, 17, 21, 17, 20, 17, ...
%e A365383 Triangle begins:
%e A365383    1
%e A365383    2   1
%e A365383    3   2   2
%e A365383    5   3   4   3
%e A365383    7   5   6   6   6
%e A365383   11   7   9   8   9   7
%e A365383   15  11  13  13  14  13  14
%e A365383   22  15  19  17  20  17  20  16
%e A365383   30  22  26  26  27  26  28  26  27
%e A365383   42  30  37  34  39  33  40  34  39  34
%e A365383   56  42  50  49  52  50  54  51  54  53  53
%e A365383   77  56  68  64  71  63  73  63  71  65  70  62
%e A365383  101  77  91  89  95  90  97  93  97  97  98  94  99
%e A365383  135 101 122 115 127 115 130 114 131 119 130 117 132 116
%e A365383  176 135 159 156 165 157 170 161 167 168 166 165 172 164 166
%e A365383 Row n = 6 counts the following partitions:
%e A365383   (6)       (51)      (51)      (51)      (51)      (51)
%e A365383   (51)      (411)     (42)      (411)     (42)      (411)
%e A365383   (42)      (321)     (411)     (33)      (411)     (321)
%e A365383   (411)     (3111)    (321)     (321)     (321)     (3111)
%e A365383   (33)      (2211)    (3111)    (3111)    (3111)    (2211)
%e A365383   (321)     (21111)   (222)     (2211)    (222)     (21111)
%e A365383   (3111)    (111111)  (2211)    (21111)   (2211)    (111111)
%e A365383   (222)               (21111)   (111111)  (21111)
%e A365383   (2211)              (111111)            (111111)
%e A365383   (21111)
%e A365383   (111111)
%t A365383 combu[n_,y_]:=With[{s=Table[{k,i},{k,Union[y]},{i,0,Floor[n/k]}]},Select[Tuples[s],Total[Times@@@#]==n&]];
%t A365383 Table[Length[Select[IntegerPartitions[n],combu[k,#]!={}&]],{n,0,12},{k,0,n-1}]
%Y A365383 Column k = 0 is A000041, strict A000009.
%Y A365383 The version for subsets is A365381, main diagonal A365376.
%Y A365383 A000041 counts integer partitions, strict A000009.
%Y A365383 A008284 counts partitions by length, strict A008289.
%Y A365383 A116861 and A364916 count linear combinations of strict partitions.
%Y A365383 A364350 counts combination-free strict partitions, non-strict A364915.
%Y A365383 A364839 counts combination-full strict partitions, non-strict A364913.
%Y A365383 Cf. A088314, A088528, A237668, A363225, A364345, A365073, A365311, A365320, A365378, A365382.
%K A365383 nonn,tabl
%O A365383 0,2
%A A365383 _Gus Wiseman_, Sep 08 2023