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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.

A321742 Irregular triangle read by rows where T(H(u),H(v)) is the coefficient of m(v) in e(u), where H is Heinz number, m is monomial symmetric functions, and e is elementary symmetric functions.

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%I A321742 #7 Nov 20 2018 12:21:19
%S A321742 1,1,0,1,1,2,0,0,1,0,1,3,0,0,0,0,1,1,3,6,0,1,0,2,6,0,0,0,1,4,0,0,0,0,
%T A321742 0,0,1,0,2,1,5,12,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,1,5,0,0,0,1,0,3,10,
%U A321742 1,6,4,12,24,0,0,0,0,0,0,0,0,0,0,0,0,0,0
%N A321742 Irregular triangle read by rows where T(H(u),H(v)) is the coefficient of m(v) in e(u), where H is Heinz number, m is monomial symmetric functions, and e is elementary symmetric functions.
%C A321742 Row n has length A000041(A056239(n)).
%C A321742 The Heinz number of an integer partition (y_1, ..., y_k) is prime(y_1) * ... * prime(y_k).
%H A321742 Wikipedia, <a href="https://en.wikipedia.org/wiki/Symmetric_polynomial">Symmetric polynomial</a>
%e A321742 Triangle begins:
%e A321742    1
%e A321742    1
%e A321742    0   1
%e A321742    1   2
%e A321742    0   0   1
%e A321742    0   1   3
%e A321742    0   0   0   0   1
%e A321742    1   3   6
%e A321742    0   1   0   2   6
%e A321742    0   0   0   1   4
%e A321742    0   0   0   0   0   0   1
%e A321742    0   2   1   5  12
%e A321742    0   0   0   0   0   0   0   0   0   0   1
%e A321742    0   0   0   0   0   1   5
%e A321742    0   0   0   1   0   3  10
%e A321742    1   6   4  12  24
%e A321742    0   0   0   0   0   0   0   0   0   0   0   0   0   0   1
%e A321742    0   0   1   5   2  12  30
%e A321742 For example, row 12 gives: e(211) = 2m(22) + m(31) + 5m(211) + 12m(1111).
%t A321742 primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
%t A321742 sps[{}]:={{}};sps[set:{i_,___}]:=Join@@Function[s,Prepend[#,s]&/@sps[Complement[set,s]]]/@Cases[Subsets[set],{i,___}];
%t A321742 mps[set_]:=Union[Sort[Sort/@(#/.x_Integer:>set[[x]])]&/@sps[Range[Length[set]]]];
%t A321742 nrmptn[n_]:=Join@@MapIndexed[Table[#2[[1]],{#1}]&,If[n==1,{},Flatten[Cases[FactorInteger[n]//Reverse,{p_,k_}:>Table[PrimePi[p],{k}]]]]];
%t A321742 Table[Table[Sum[Times@@Factorial/@Length/@Split[Sort[Length/@mtn,Greater]]/Times@@Factorial/@Length/@Split[mtn],{mtn,Select[mps[nrmptn[n]],And[And@@UnsameQ@@@#,Sort[Length/@#]==primeMS[k]]&]}],{k,Sort[Times@@Prime/@#&/@IntegerPartitions[Total[primeMS[n]]]]}],{n,18}]
%Y A321742 Row sums are A321743.
%Y A321742 Cf. A008480, A049311, A056239, A116540, A124794, A124795, A300121, A319193, A321738, A321742-A321765, A321854.
%K A321742 nonn,tabf
%O A321742 1,6
%A A321742 _Gus Wiseman_, Nov 19 2018