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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.

A321895 Irregular triangle read by rows where T(H(u),H(v)) is the coefficient of p(v) in M(u), where H is Heinz number, M is augmented monomial symmetric functions, and p is power sum symmetric functions.

Original entry on oeis.org

1, 1, 1, 0, -1, 1, 1, 0, 0, -1, 1, 0, 1, 0, 0, 0, 0, 2, -3, 1, -1, 1, 0, 0, 0, -1, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 2, -1, -2, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 1, 0, 0, 0, 0, 0, -1, 0, 1, 0, 0, 0, 0, -6, 3, 8, -6, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
Offset: 1

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Author

Gus Wiseman, Nov 20 2018

Keywords

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).
The augmented monomial symmetric functions are given by M(y) = c(y) * m(y) where c(y) = Product_i (y)_i! where (y)_i is the number of i's in y and m is monomial symmetric functions.

Examples

			Triangle begins:
   1
   1
   1   0
  -1   1
   1   0   0
  -1   1   0
   1   0   0   0   0
   2  -3   1
  -1   1   0   0   0
  -1   0   1   0   0
   1   0   0   0   0   0   0
   2  -1  -2   1   0
   1   0   0   0   0   0   0   0   0   0   0
  -1   1   0   0   0   0   0
  -1   0   1   0   0   0   0
  -6   3   8  -6   1
   1   0   0   0   0   0   0   0   0   0   0   0   0   0   0
   2  -1  -2   1   0   0   0
For example, row 12 gives: M(211) = 2p(4) - p(22) - 2p(31) + p(211).
		

Crossrefs

Programs

  • 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,_}];
    Table[Sum[Product[(-1)^(Length[t]-1)*(Length[t]-1)!,{t,s}],{s,Select[sps[Range[PrimeOmega[n]]]/.Table[i->If[n==1,{},primeMS[n]][[i]],{i,PrimeOmega[n]}],Times@@Prime/@Total/@#==m&]}],{n,18},{m,Sort[Times@@Prime/@#&/@IntegerPartitions[Total[primeMS[n]]]]}]