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.
%I A306186 #11 May 11 2021 17:22:31 %S A306186 1,2,1,3,4,1,5,10,6,1,7,33,21,8,1,11,91,104,36,10,1,15,298,452,238,55, %T A306186 12,1,22,910,2335,1430,455,78,14,1,30,3017,11992,10179,3505,775,105, %U A306186 16,1,42,9945,66810,74299,31881,7297,1218,136,18,1,56 %N A306186 Array read by antidiagonals upwards where A(n, k) is the number of non-isomorphic multiset partitions of weight n with k levels of brackets. %e A306186 Array begins: %e A306186 k=1: k=2: k=3: k=4: k=5: k=6: %e A306186 n=1: 1 1 1 1 1 1 %e A306186 n=2: 2 4 6 8 10 12 %e A306186 n=3: 3 10 21 36 55 78 %e A306186 n=4: 5 33 104 238 455 775 %e A306186 n=5: 7 91 452 1430 3505 7297 %e A306186 n=6: 11 298 2335 10179 31881 80897 %e A306186 Non-isomorphic representatives of the A(3,3) = 21 multiset partitions: %e A306186 {{111}} {{112}} {{123}} %e A306186 {{1}{11}} {{1}{12}} {{1}{23}} %e A306186 {{1}}{{11}} {{2}{11}} {{1}}{{23}} %e A306186 {{1}{1}{1}} {{1}}{{12}} {{1}{2}{3}} %e A306186 {{1}}{{1}{1}} {{1}{1}{2}} {{1}}{{2}{3}} %e A306186 {{1}}{{1}}{{1}} {{2}}{{11}} {{1}}{{2}}{{3}} %e A306186 {{1}}{{1}{2}} %e A306186 {{2}}{{1}{1}} %e A306186 {{1}}{{1}}{{2}} %t A306186 sps[{}]:={{}};sps[set:{i_,___}]:=Join@@Function[s,Prepend[#,s]&/@sps[Complement[set,s]]]/@Cases[Subsets[set],{i,___}]; %t A306186 mps[set_]:=Union[Sort[Sort/@(#/.x_Integer:>set[[x]])]&/@sps[Range[Length[set]]]]; %t A306186 undats[m_]:=Union[DeleteCases[Cases[m,_?AtomQ,{0,Infinity},Heads->True],List]]; %t A306186 expnorm[m_]:=If[Length[undats[m]]==0,m,If[undats[m]!=Range[Max@@undats[m]],expnorm[m/.Apply[Rule,Table[{undats[m][[i]],i},{i,Length[undats[m]]}],{1}]],First[Sort[expnorm[m,1]]]]]; %t A306186 expnorm[m_,aft_]:=If[Length[undats[m]]<=aft,{m},With[{mx=Table[Count[m,i,{0,Infinity},Heads->True],{i,Select[undats[m],#1>=aft&]}]},Union@@(expnorm[#1,aft+1]&)/@Union[Table[MapAt[Sort,m/.{par+aft-1->aft,aft->par+aft-1},Position[m,_[___]]],{par,First/@Position[mx,Max[mx]]}]]]]; %t A306186 strnorm[n_]:=(Flatten[MapIndexed[Table[#2,{#1}]&,#1]]&)/@IntegerPartitions[n]; %t A306186 kmp[n_,k_]:=kmp[n,k]=If[k==1,strnorm[n],Union[expnorm/@Join@@mps/@kmp[n,k-1]]]; %t A306186 Table[Length[kmp[sum-k,k]],{sum,1,7},{k,1,sum-1}] %Y A306186 Columns: A000041 (k=1), A007716 (k=2), A318566 (k=3). %Y A306186 Rows: A000012 (n=1), A005843 (n=2), A014105 (n=3). %Y A306186 Cf. A002846, A096751, A144150, A290353, A317533, A317791, A323718, A323719. %K A306186 nonn,tabl,more %O A306186 1,2 %A A306186 _Gus Wiseman_, Jan 27 2019 %E A306186 a(46)-a(56) from _Robert Price_, May 11 2021