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A319557 Number of non-isomorphic strict connected multiset partitions of weight n. 29

%I #16 Jan 21 2023 17:58:25

%S 1,1,2,5,12,30,91,256,823,2656,9103,31876,116113,432824,1659692,

%T 6508521,26112327,106927561,446654187,1900858001,8236367607,

%U 36306790636,162724173883,741105774720,3428164417401,16099059101049,76722208278328,370903316203353,1818316254655097

%N Number of non-isomorphic strict connected multiset partitions of weight n.

%C The weight of a multiset partition is the sum of sizes of its parts. Weight is generally not the same as number of vertices.

%C Also the number of non-isomorphic connected T_0 multiset partitions of weight n. In a multiset partition, two vertices are equivalent if in every block the multiplicity of the first is equal to the multiplicity of the second. The T_0 condition means that there are no equivalent vertices.

%H Andrew Howroyd, <a href="/A319557/b319557.txt">Table of n, a(n) for n = 0..50</a>

%F Inverse Euler transform of A316980.

%e Non-isomorphic representatives of the a(4) = 12 strict connected multiset partitions:

%e {{1,1,1,1}}

%e {{1,1,2,2}}

%e {{1,2,2,2}}

%e {{1,2,3,3}}

%e {{1,2,3,4}}

%e {{1},{1,1,1}}

%e {{1},{1,2,2}}

%e {{2},{1,2,2}}

%e {{3},{1,2,3}}

%e {{1,2},{2,2}}

%e {{1,3},{2,3}}

%e {{1},{2},{1,2}}

%e Non-isomorphic representatives of the a(4) = 12 connected T_0 multiset partitions:

%e {{1,1,1,1}}

%e {{1,2,2,2}}

%e {{1},{1,1,1}}

%e {{1},{1,2,2}}

%e {{2},{1,2,2}}

%e {{1,1},{1,1}}

%e {{1,2},{2,2}}

%e {{1,3},{2,3}}

%e {{1},{1},{1,1}}

%e {{1},{2},{1,2}}

%e {{2},{2},{1,2}}

%e {{1},{1},{1},{1}}

%Y Cf. A007716, A007718, A049311, A056156, A283877, A316980.

%Y Cf. A319558, A319559, A319560, A319564, A319565, A319566, A319567.

%K nonn

%O 0,3

%A _Gus Wiseman_, Sep 23 2018

%E Terms a(11) and beyond from _Andrew Howroyd_, Jan 19 2023

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Last modified April 23 10:29 EDT 2024. Contains 371905 sequences. (Running on oeis4.)