cp's OEIS Frontend

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.

A321854 Irregular triangle where T(H(u),H(v)) is the number of ways to partition the Young diagram of u into vertical sections whose sizes are the parts of v, where H is Heinz number.

This page as a plain text file.
%I A321854 #9 Feb 04 2019 07:37:34
%S A321854 1,1,0,1,1,1,0,0,1,0,2,1,0,0,0,0,1,1,3,1,0,2,0,4,1,0,0,0,3,1,0,0,0,0,
%T A321854 0,0,1,0,2,2,5,1,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,4,1,0,0,0,6,0,6,1,1,
%U A321854 3,4,6,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1
%N A321854 Irregular triangle where T(H(u),H(v)) is the number of ways to partition the Young diagram of u into vertical sections whose sizes are the parts of v, where H is Heinz number.
%C A321854 Row n has length A000041(A056239(n)).
%C A321854 A vertical section is a partial Young diagram with at most one square in each row.
%e A321854 Triangle begins:
%e A321854   1
%e A321854   1
%e A321854   0  1
%e A321854   1  1
%e A321854   0  0  1
%e A321854   0  2  1
%e A321854   0  0  0  0  1
%e A321854   1  3  1
%e A321854   0  2  0  4  1
%e A321854   0  0  0  3  1
%e A321854   0  0  0  0  0  0  1
%e A321854   0  2  2  5  1
%e A321854   0  0  0  0  0  0  0  0  0  0  1
%e A321854   0  0  0  0  0  4  1
%e A321854   0  0  0  6  0  6  1
%e A321854   1  3  4  6  1
%e A321854   0  0  0  0  0  0  0  0  0  0  0  0  0  0  1
%e A321854   0  0  4 10  4  8  1
%e A321854 The 12th row counts the following partitions of the Young diagram of (211) into vertical sections (shown as colorings by positive integers):
%e A321854   T(12,7) = 0:
%e A321854 .
%e A321854   T(12,9) = 2:    1 2   1 2
%e A321854                   1     2
%e A321854                   2     1
%e A321854 .
%e A321854   T(12,10) = 2:   1 2   1 2
%e A321854                   2     1
%e A321854                   2     1
%e A321854 .
%e A321854   T(12,12) = 5:   1 2   1 2   1 2   1 2   1 2
%e A321854                   3     2     3     1     3
%e A321854                   3     3     2     3     1
%e A321854 .
%e A321854   T(12,16) = 1:   1 2
%e A321854                   3
%e A321854                   4
%t A321854 primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
%t A321854 spsu[_,{}]:={{}};spsu[foo_,set:{i_,___}]:=Join@@Function[s,Prepend[#,s]&/@spsu[Select[foo,Complement[#,Complement[set,s]]=={}&],Complement[set,s]]]/@Cases[foo,{i,___}];
%t A321854 ptnpos[y_]:=Position[Table[1,{#}]&/@y,1];
%t A321854 ptnverts[y_]:=Select[Rest[Subsets[ptnpos[y]]],UnsameQ@@First/@#&];
%t A321854 Table[With[{y=Reverse[primeMS[n]]},Table[Length[Select[spsu[ptnverts[y],ptnpos[y]],Sort[Length/@#]==primeMS[k]&]],{k,Sort[Times@@Prime/@#&/@IntegerPartitions[Total[primeMS[n]]]]}]],{n,18}]
%Y A321854 Cf. A000085, A000110, A007016, A056239, A122111, A153452, A215366, A296188, A300121, A318396, A321719-A321731, A321737, A321738, A321742-A321765.
%K A321854 nonn,tabf
%O A321854 1,11
%A A321854 _Gus Wiseman_, Nov 19 2018