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A366745 Triangular array, read by rows: T(n,k) = number of partitions p of n such that d(p, p') = 2k, where p' = contraconjugate of p, and d is the distance function defined in A366156.

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%I A366745 #10 Nov 12 2023 22:00:53
%S A366745 1,0,2,1,0,2,1,2,0,2,1,2,2,0,2,1,0,6,2,0,2,1,2,2,6,2,0,2,0,6,2,4,6,2,
%T A366745 0,2,0,2,4,8,6,6,2,0,2,0,4,8,8,8,4,6,2,0,2,0,6,10,8,12,6,4,6,2,0,2,1,
%U A366745 4,14,8,16,10,6,6,8,2,0,2,1,4,18,10,14,20,10,6,6,8,2,0,2,1,8,8,18,20,22,16,16,6,8,8,2,0,2,0,6,18,28,30,24,16,16,10,8,8,8,2,0,2,1,4,20,28,30,36,16,34,18,16,4,12,8,2,0,2
%N A366745 Triangular array, read by rows: T(n,k) = number of partitions p of n such that d(p, p') = 2k, where p' = contraconjugate of p, and d is the distance function defined in A366156.
%C A366745 Let RL denote reverse lexicographic. Write each partition p of n in RL order, and then arrange all the partitions of n in RL order, obtaining a list L as in Mathematica's IntegerPartitions[n].  Let L' be the reversal of L. Let p(i) be the i-th partition in L and let p'(i) be the i-th in L'; then p'(i) is introduced here as the contraconjugate of p(i) . (Note that RL order could be called "greedy" order, because the result of applying the greedy algorithm to p is the same as for RL, and likewise for arranging the partitions in RL order. For a discussion of various orderings, see A080577.)
%e A366745 First 14 rows:
%e A366745   1
%e A366745   0    2
%e A366745   1    0    2
%e A366745   1    2    0    2
%e A366745   1    2    2    0    2
%e A366745   1    0    6    2    0    2
%e A366745   1    2    2    6    2    0    2
%e A366745   0    6    2    4    6    2    0    2
%e A366745   0    2    4    8    6    6    2    0    2
%e A366745   0    4    8    8    8    4    6    2    0    2
%e A366745   0    6   10    8   12    6    4    6    2    0    2
%e A366745   1    4   14    8   16   10    6    6    8    2    0    2
%e A366745   1    4   18   10   14   20   10    6    6    8    2    0    2
%e A366745   1    8    8   18   20   22   16   16    6    8    8    2    0    2
%e A366745 The list L for the partitions of 5 is:
%e A366745   [5], [4,1], [3,2], [3,1,1], [2,2,1], [2,1,1,1], [1,1,1,1,1].
%e A366745 The list L' of contraconjugates p' and distances d(p,p') are given by:
%e A366745   p = [5]; p' = [1,1,1,1,1]; d(p,p') = 8
%e A366745   p = [4,1]; p' = [2,1,1,1]; d(p,p') = 4
%e A366745   p = [3,2]; p' = [2,2,1]; d(p,p') = 2
%e A366745   p = [3,1,1,1]; p' = [3,1,1,1]; d(p,p') = 0
%e A366745   p = [2,2,1]; p' = [3,2]; d(p,p') = 2
%e A366745   p = [2,1,1,1]; p' = [4,1]; d(p,p') = 4
%e A366745   p = [1,1,1,1,1], p' = [5]; d(p,p') = 8;
%e A366745 so that the numbers of 0s, 2s, 4s, 6s, 8s are 1, 2, 2, 0, 2, as in row 5.
%t A366745 c[n_] := PartitionsP[n];
%t A366745 p[n_, k_] := p[n, k] = IntegerPartitions[n][[k]];
%t A366745 r[n_, k_] := r[n, k] = Join[p[n, k], ConstantArray[0, n - Length[p[n, k]]]];
%t A366745 p1[n_, k_] := p1[n, k] = Reverse[IntegerPartitions[n]][[k]];
%t A366745 r1[n_, k_] := r1[n, k] = Join[p1[n, k], ConstantArray[0, n - Length[p1[n, k]]]];
%t A366745 d[u_, v_] := Total[Abs[u - v]];
%t A366745 t[n_] := Flatten[Table[d[r[n, k], r1[n, k]], {k, 1, c[n]}]];
%t A366745 t1 = Table[Count[t[n], m], {n, 1, 16}, {m, 0, 2 n - 1, 2}]
%t A366745 TableForm[t1]   (* array *)
%t A366745 u = Flatten[t1] (*sequence *)
%Y A366745 Cf. A000041, A366156, A366746.
%K A366745 nonn,tabl
%O A366745 1,3
%A A366745 _Clark Kimberling_, Oct 25 2023