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A325406 Triangle read by rows where T(n,k) is the number of reversed integer partitions of n with k distinct differences of any degree.

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%I A325406 #5 May 03 2019 21:25:36
%S A325406 1,0,1,0,1,1,0,1,2,0,0,1,2,2,0,0,1,1,3,2,0,0,1,4,2,3,1,0,0,1,1,5,5,2,
%T A325406 1,0,0,1,3,5,6,3,3,1,0,0,1,3,4,8,7,1,4,2,0,0,1,3,6,11,7,5,2,4,2,1,0,1,
%U A325406 1,6,13,8,9,9,0,4,3,1,0,1,6,7,11,12,9
%N A325406 Triangle read by rows where T(n,k) is the number of reversed integer partitions of n with k distinct differences of any degree.
%C A325406 The differences of a sequence are defined as if the sequence were increasing, so for example the differences of (6,3,1) are (-3,-2).
%C A325406 The zeroth differences of a sequence are the sequence itself, while the k-th differences for k > 0 are the differences of the (k-1)-th differences. The distinct differences of any degree are the union of the k-th differences for all k >= 0. For example, the k-th differences of (1,1,2,4) for k = 0...3 are:
%C A325406   (1,1,2,4)
%C A325406   (0,1,2)
%C A325406   (1,1)
%C A325406   (0)
%C A325406 so there are a total of 4 distinct differences of any degree, namely {0,1,2,4}.
%H A325406 Gus Wiseman, <a href="/A325325/a325325.txt">Sequences counting and ranking integer partitions by the differences of their successive parts.</a>
%e A325406 Triangle begins:
%e A325406   1
%e A325406   0  1
%e A325406   0  1  1
%e A325406   0  1  2  0
%e A325406   0  1  2  2  0
%e A325406   0  1  1  3  2  0
%e A325406   0  1  4  2  3  1  0
%e A325406   0  1  1  5  5  2  1  0
%e A325406   0  1  3  5  6  3  3  1  0
%e A325406   0  1  3  4  8  7  1  4  2  0
%e A325406   0  1  3  6 11  7  5  2  4  2  1
%e A325406   0  1  1  6 13  8  9  9  0  4  3  1
%e A325406   0  1  6  7 11 12  9 10  8  4  3  2  2
%e A325406   0  1  1  7 18  9 14 19  5 10  3  5  4  1
%e A325406   0  1  3  9 17  9 22 20 15  9  7  6  5  4  1
%e A325406   0  1  4  8 22 11 16 24 22 19 10 11  2  8  7  2
%e A325406   0  1  4 10 23 15 24 23 27 27 12 14 11  8  8  5  5
%e A325406 Row n = 8 counts the following partitions:
%e A325406   (8)  (44)        (17)       (116)     (134)   (1133)   (111122)
%e A325406        (2222)      (26)       (125)     (233)   (11123)
%e A325406        (11111111)  (35)       (1115)    (1223)  (11222)
%e A325406                    (224)      (1124)
%e A325406                    (1111112)  (11114)
%e A325406                               (111113)
%t A325406 Table[Length[Select[Reverse/@IntegerPartitions[n],Length[Union@@Table[Differences[#,i],{i,0,Length[#]}]]==k&]],{n,0,16},{k,0,n}]
%Y A325406 Row sums are A000041.
%Y A325406 Cf. A049597, A049988, A279945, A320348, A325324, A325325, A325349, A325404, A325466.
%K A325406 nonn,tabl
%O A325406 0,9
%A A325406 _Gus Wiseman_, May 03 2019