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A325336 Triangle read by rows where T(n,k) is the number of integer partitions of n with adjusted frequency depth k whose parts cover an initial interval of positive integers.

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%I A325336 #8 Jan 19 2023 02:04:24
%S A325336 1,0,1,0,0,1,0,0,1,1,0,0,1,0,1,0,0,1,0,2,0,0,0,1,2,1,0,0,0,0,1,0,3,1,
%T A325336 0,0,0,0,1,0,3,2,0,0,0,0,0,1,1,3,3,0,0,0,0,0,0,1,1,5,3,0,0,0,0,0,0,0,
%U A325336 1,0,8,3,0,0,0,0,0,0,0,0,1,2,6,6,0,0,0
%N A325336 Triangle read by rows where T(n,k) is the number of integer partitions of n with adjusted frequency depth k whose parts cover an initial interval of positive integers.
%C A325336 The adjusted frequency depth of an integer partition (A325280) is 0 if the partition is empty, and otherwise it is 1 plus the number of times one must take the multiset of multiplicities to reach a singleton. For example, the partition (32211) has adjusted frequency depth 5 because we have: (32211) -> (221) -> (21) -> (11) -> (2).
%H A325336 Andrew Howroyd, <a href="/A325336/b325336.txt">Table of n, a(n) for n = 0..1325</a> (rows 0..50)
%e A325336 Triangle begins:
%e A325336   1
%e A325336   0  1
%e A325336   0  0  1
%e A325336   0  0  1  1
%e A325336   0  0  1  0  1
%e A325336   0  0  1  0  2  0
%e A325336   0  0  1  2  1  0  0
%e A325336   0  0  1  0  3  1  0  0
%e A325336   0  0  1  0  3  2  0  0  0
%e A325336   0  0  1  1  3  3  0  0  0  0
%e A325336   0  0  1  1  5  3  0  0  0  0  0
%e A325336   0  0  1  0  8  3  0  0  0  0  0  0
%e A325336   0  0  1  2  6  6  0  0  0  0  0  0  0
%e A325336   0  0  1  0 13  4  0  0  0  0  0  0  0  0
%e A325336   0  0  1  0 12  8  1  0  0  0  0  0  0  0  0
%e A325336   0  0  1  2 14  7  3  0  0  0  0  0  0  0  0  0
%e A325336   0  0  1  0 17 11  3  0  0  0  0  0  0  0  0  0  0
%e A325336   0  0  1  0 22  7  8  0  0  0  0  0  0  0  0  0  0  0
%e A325336   0  0  1  2 17 16 10  0  0  0  0  0  0  0  0  0  0  0  0
%e A325336   0  0  1  0 28 10 15  0  0  0  0  0  0  0  0  0  0  0  0  0
%e A325336   0  0  1  1 29 13 20  0  0  0  0  0  0  0  0  0  0  0  0  0  0
%e A325336 Row 15 counts the following partitions:
%e A325336   111111111111111  54321       433221          333321        4322211
%e A325336                    2222211111  443211          3332211       4332111
%e A325336                                3322221         33222111      43221111
%e A325336                                22222221        322221111
%e A325336                                32222211        332211111
%e A325336                                33321111        432111111
%e A325336                                222222111       321111111111
%e A325336                                3222111111
%e A325336                                3321111111
%e A325336                                22221111111
%e A325336                                32211111111
%e A325336                                222111111111
%e A325336                                2211111111111
%e A325336                                21111111111111
%t A325336 normQ[m_]:=Or[m=={},Union[m]==Range[Max[m]]];
%t A325336 fdadj[ptn_List]:=If[ptn=={},0,Length[NestWhileList[Sort[Length/@Split[#1]]&,ptn,Length[#1]>1&]]];
%t A325336 Table[Length[Select[IntegerPartitions[n],normQ[#]&&fdadj[#]==k&]],{n,0,30},{k,0,n}]
%o A325336 (PARI)
%o A325336 depth(p)={if(!#p, 0, my(r=1); while(#p > 1, my(L=List(), k=0); for(i=1, #p, if(i==#p||p[i]<>p[i+1], listput(L,i-k); k=i)); listsort(L); p=L; r++); r)}
%o A325336 isok(p)={if(#p, for(i=1, #p, if(p[i]-1 > if(i>1, p[i-1], 0), return(0)))); 1}
%o A325336 row(n)={my(v=vector(1+n)); forpart(p=n, if(isok(p), v[1+depth(Vec(p))]++)); v}
%o A325336 { for(n=0, 10, print(row(n))) } \\ _Andrew Howroyd_, Jan 18 2023
%Y A325336 Row sums are A000009.
%Y A325336 Column k = 3 is A325334.
%Y A325336 Column k = 4 is A325335.
%Y A325336 Cf. A181819, A182850, A317246, A320348, A323014, A325280, A325372.
%K A325336 nonn,tabl
%O A325336 0,20
%A A325336 _Gus Wiseman_, May 01 2019