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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.

A321155 Regular triangle where T(n,k) is the number of non-isomorphic connected multiset partitions of weight n with density -1 <= k < n-2.

Original entry on oeis.org

1, 2, 1, 3, 2, 1, 6, 6, 4, 1, 10, 14, 11, 4, 1, 22, 38, 38, 20, 6, 1, 42, 94, 111, 72, 28, 6, 1, 94, 250, 348, 278, 138, 42, 8, 1, 203, 648, 1044, 992, 596, 226, 56, 8, 1, 470, 1728, 3192, 3538, 2536, 1192, 370, 76, 10, 1
Offset: 1

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Author

Gus Wiseman, Oct 29 2018

Keywords

Comments

The density of a multiset partition of weight n with e parts and v vertices is n - e - v. The weight of a multiset partition is the sum of sizes of its parts.

Examples

			Triangle begins:
    1
    2    1
    3    2    1
    6    6    4    1
   10   14   11    4    1
   22   38   38   20    6    1
   42   94  111   72   28    6    1
   94  250  348  278  138   42    8    1
  203  648 1044  992  596  226   56    8    1
  470 1728 3192 3538 2536 1192  370   76   10    1
Non-isomorphic representatives of the connected multiset partitions counted in row 5:
{1,2,3,4,5}         {1,2,3,4,4}       {1,2,2,3,3}     {1,1,2,2,2}   {1,1,1,1,1}
{1,4},{2,3,4}       {1,2},{2,3,3}     {1,2,3,3,3}     {1,2,2,2,2}
{4},{1,2,3,4}       {1,3},{2,3,3}     {1,1},{1,2,2}   {1},{1,1,1,1}
{2},{1,3},{2,3}     {2},{1,2,3,3}     {1},{1,2,2,2}   {1,1},{1,1,1}
{2},{3},{1,2,3}     {2,3},{1,2,3}     {1,2},{1,2,2}
{3},{1,3},{2,3}     {3},{1,2,3,3}     {1,2},{2,2,2}
{3},{3},{1,2,3}     {3,3},{1,2,3}     {2},{1,1,2,2}
{1},{2},{2},{1,2}   {1},{1},{1,2,2}   {2},{1,2,2,2}
{2},{2},{2},{1,2}   {1},{1,2},{2,2}   {2,2},{1,2,2}
{1},{1},{1},{1},{1} {1},{2},{1,2,2}   {1},{1},{1,1,1}
                    {2},{1,2},{1,2}   {1},{1,1},{1,1}
                    {2},{1,2},{2,2}
                    {2},{2},{1,2,2}
                    {1},{1},{1},{1,1}
		

Crossrefs

First column is A125702. Row sums are A007718.