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A321744 Irregular triangle read by rows where T(H(u),H(v)) is the coefficient of m(v) in h(u), where H is Heinz number, m is monomial symmetric functions, and h is homogeneous symmetric functions. 2
1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 3, 1, 1, 1, 1, 1, 1, 3, 6, 1, 3, 2, 4, 6, 1, 2, 2, 3, 4, 1, 1, 1, 1, 1, 1, 1, 1, 4, 3, 7, 12, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 3, 3, 4, 5, 1, 2, 3, 5, 4, 7, 10, 1, 6, 4, 12, 24, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,6
COMMENTS
Row n has length A000041(A056239(n)).
The Heinz number of an integer partition (y_1, ..., y_k) is prime(y_1) * ... * prime(y_k).
Also the number of size-preserving permutations of type-v multiset partitions of a multiset whose multiplicities are the parts of u.
Also the coefficient of f(v) in e(u), where e is elementary symmetric functions and f is forgotten symmetric functions.
LINKS
EXAMPLE
Triangle begins:
1
1
1 1
1 2
1 1 1
1 2 3
1 1 1 1 1
1 3 6
1 3 2 4 6
1 2 2 3 4
1 1 1 1 1 1 1
1 4 3 7 12
1 1 1 1 1 1 1 1 1 1 1
1 2 2 3 3 4 5
1 2 3 5 4 7 10
1 6 4 12 24
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
1 3 5 11 8 18 30
For example, row 12 gives: h(211) = m(4) + 4m(22) + 3m(31) + 7m(211) + 12m(1111).
MATHEMATICA
primeMS[n_]:=If[n==1, {}, Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]];
sps[{}]:={{}}; sps[set:{i_, ___}]:=Join@@Function[s, Prepend[#, s]&/@sps[Complement[set, s]]]/@Cases[Subsets[set], {i, ___}];
mps[set_]:=Union[Sort[Sort/@(#/.x_Integer:>set[[x]])]&/@sps[Range[Length[set]]]];
nrmptn[n_]:=Join@@MapIndexed[Table[#2[[1]], {#1}]&, If[n==1, {}, Flatten[Cases[FactorInteger[n]//Reverse, {p_, k_}:>Table[PrimePi[p], {k}]]]]];
Table[Table[Sum[Times@@Factorial/@Length/@Split[Sort[Length/@mtn, Greater]]/Times@@Factorial/@Length/@Split[mtn], {mtn, Select[mps[nrmptn[n]], Sort[Length/@#]==primeMS[k]&]}], {k, Sort[Times@@Prime/@#&/@IntegerPartitions[Total[primeMS[n]]]]}], {n, 18}]
CROSSREFS
Row sums are A321745.
Sequence in context: A302247 A026791 A080576 * A322763 A213211 A294775
KEYWORD
nonn,tabf
AUTHOR
Gus Wiseman, Nov 19 2018
STATUS
approved

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Last modified April 25 08:27 EDT 2024. Contains 371964 sequences. (Running on oeis4.)