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A239319 Irregular triangular array:  t(n,k) = number of times that the k-th condensed partition (in Mathematica order) of n occurs in the list of all the condensed partitions of n. 1
1, 2, 2, 1, 3, 1, 1, 2, 2, 3, 4, 1, 4, 1, 1, 2, 3, 3, 5, 1, 1, 4, 1, 6, 3, 1, 2, 3, 1, 1, 3, 3, 3, 6, 2, 5, 1, 1, 5, 1, 4, 2, 6, 3, 1, 10, 2, 2, 2, 4, 1, 1, 2, 2, 2, 3, 5, 7, 2, 5, 1, 1, 7, 5, 6, 5, 1, 1, 4, 1, 6, 1, 6, 4, 2, 9, 3, 2, 3, 2, 4, 3, 10, 6, 1, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Suppose that p is a partition of n.  Let x(1), x(2), ..., x(k) be the distinct parts of p, and let m(i) be the multiplicity of x(i) in p.  Let c(p) be the partition {m(1)*x(1), m(2)*x(2), ... , x(k)*m(k)} of n.  As defined at A239312, a partition q of n is a condensed partition n if q = f(p) for some partition p of n.  The number of numbers in row n is A239312(n); (sum of numbers in row n) = A000041(n), and column 1 is given by A000005.

LINKS

Clark Kimberling, Table of n, a(n) for n = 1..1000

EXAMPLE

The partitions of 6 are 6, 51, 42, 411, 33, 321, 3111, 222, 2211, 21111, 111111, with respective condensations 6, 51, 42, 42, 6, 321, 33, 6, 42, 42, 6.  There are A239312(6) = 5 of these, listed here in Mathematica order (x(1) >= x(2) >= ... ):  6, 51, 42, 33, 321.  These occur in the list of condensed partitions with multiplicities 4, 1, 4, 1, 1, which is row 6 of the array.  First 9 rows:

1

2

2 1

3 1 1

2 2 3

4 1 4 1 1

2 3 3 5 1 1

4 1 6 3 1 2 3 1 1

3 3 3 6 2 5 1 1 5 1

MATHEMATICA

z = 15; u[n_, k_] := u[n, k] = Map[Total, Split[IntegerPartitions[n][[k]]]]; r[n_] := r[n] = Table[Reverse[Sort[u[n, k]]], {k, 1, PartitionsP[n]}] ; t[n_] := t[n] = DeleteDuplicates[r[n]]; u[n_] := u[n] = Length[t[n]] ; v = Table[Count[r[n], t[n][[k]]], {n, 1, z}, {k, 1, u[n]}]; TableForm[v] (* A239319, array *)

Flatten[v] (* A239319, sequence *)

CROSSREFS

A000041, A239312.

Sequence in context: A236293 A056044 A236097 * A236468 A116685 A268190

Adjacent sequences:  A239316 A239317 A239318 * A239320 A239321 A239322

KEYWORD

nonn,tabf,easy

AUTHOR

Clark Kimberling, Mar 15 2014

STATUS

approved

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Last modified July 26 00:44 EDT 2017. Contains 289798 sequences.