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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.

A323719 Array read by antidiagonals upwards where A(n, k) is the number of orderless factorizations of n with k - 1 levels of parentheses.

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%I A323719 #8 Jan 27 2019 18:02:29
%S A323719 1,1,1,1,1,1,1,1,1,1,1,2,1,1,1,1,1,3,1,1,1,1,2,1,4,1,1,1,1,1,3,1,5,1,
%T A323719 1,1,1,3,1,4,1,6,1,1,1,1,2,6,1,5,1,7,1,1,1,1,2,3,10,1,6,1,8,1,1,1,1,1,
%U A323719 3,4,15,1,7,1,9,1,1,1,1,4,1,4,5,21,1,8,1,10,1,1,1
%N A323719 Array read by antidiagonals upwards where A(n, k) is the number of orderless factorizations of n with k - 1 levels of parentheses.
%C A323719 An orderless factorization of n with k > 1 levels of parentheses is any multiset partition of an orderless factorization of n with k - 1 levels of parentheses. If k = 1 it is just an orderless factorization of n into factors > 1.
%e A323719 Array begins:
%e A323719        k=0  k=1  k=2  k=3  k=4  k=5  k=6  k=7  k=8  k=9  k=10 k=11 k=12
%e A323719    n=1: 1    1    1    1    1    1    1    1    1    1    1    1    1
%e A323719    n=2: 1    1    1    1    1    1    1    1    1    1    1    1    1
%e A323719    n=3: 1    1    1    1    1    1    1    1    1    1    1    1    1
%e A323719    n=4: 1    2    3    4    5    6    7    8    9   10   11   12   13
%e A323719    n=5: 1    1    1    1    1    1    1    1    1    1    1    1    1
%e A323719    n=6: 1    2    3    4    5    6    7    8    9   10   11   12   13
%e A323719    n=7: 1    1    1    1    1    1    1    1    1    1    1    1    1
%e A323719    n=8: 1    3    6   10   15   21   28   36   45   55   66   78   91
%e A323719    n=9: 1    2    3    4    5    6    7    8    9   10   11   12   13
%e A323719   n=10: 1    2    3    4    5    6    7    8    9   10   11   12   13
%e A323719   n=11: 1    1    1    1    1    1    1    1    1    1    1    1    1
%e A323719   n=12: 1    4    9   16   25   36   49   64   81  100  121  144  169
%e A323719   n=13: 1    1    1    1    1    1    1    1    1    1    1    1    1
%e A323719   n=14: 1    2    3    4    5    6    7    8    9   10   11   12   13
%e A323719   n=15: 1    2    3    4    5    6    7    8    9   10   11   12   13
%e A323719   n=16: 1    5   14   30   55   91  140  204  285  385  506  650  819
%e A323719   n=17: 1    1    1    1    1    1    1    1    1    1    1    1    1
%e A323719   n=18: 1    4    9   16   25   36   49   64   81  100  121  144  169
%e A323719 The A(12,3) = 16 orderless factorizations of 12 with 2 levels of parentheses:
%e A323719   ((2*2*3))          ((2*6))      ((3*4))      ((12))
%e A323719   ((2)*(2*3))        ((2)*(6))    ((3)*(4))
%e A323719   ((3)*(2*2))        ((2))*((6))  ((3))*((4))
%e A323719   ((2))*((2*3))
%e A323719   ((2)*(2)*(3))
%e A323719   ((3))*((2*2))
%e A323719   ((2))*((2)*(3))
%e A323719   ((3))*((2)*(2))
%e A323719   ((2))*((2))*((3))
%t A323719 facs[n_]:=If[n<=1,{{}},Join@@Table[Map[Prepend[#,d]&,Select[facs[n/d],Min@@#>=d&]],{d,Rest[Divisors[n]]}]];
%t A323719 lev[n_,k_]:=If[k==0,{n},Join@@Table[Union[Sort/@Tuples[lev[#,k-1]&/@fac]],{fac,facs[n]}]];
%t A323719 Table[Length[lev[sum-k,k]],{sum,12},{k,0,sum-1}]
%Y A323719 Columns: A001055 (k=1), A050336 (k=2), A050338 (k=3), A050340 (k=4).
%Y A323719 Rows: A000027, A000217, A000290, etc.
%Y A323719 Cf. A096751, A141268, A144150, A213427, A255906, A281113, A290353, A292504, A317145, A318564, A318565, A318812, A323718.
%K A323719 nonn,tabl
%O A323719 1,12
%A A323719 _Gus Wiseman_, Jan 25 2019