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A325242 Irregular triangle read by rows with zeros removed where T(n,k) is the number of integer partitions of n with k distinct multiplicities, n > 0. 32
1, 2, 3, 4, 1, 4, 3, 8, 3, 6, 9, 10, 12, 11, 19, 15, 26, 1, 13, 39, 4, 25, 47, 5, 19, 70, 12, 29, 89, 17, 33, 115, 28, 42, 148, 41, 39, 189, 69, 62, 235, 88, 55, 294, 141, 81, 362, 183, 1, 84, 450, 253, 5, 103, 558, 333, 8, 105, 669, 464, 17, 153, 817, 576, 29 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

For example, the partition (32111) has multiplicities {1,1,3}, of which 2 are distinct, so is counted under T(8,2).

LINKS

Alois P. Heinz, Rows n = 1..200, flattened

EXAMPLE

Triangle begins:

1

2

3

4 1

4 3

8 3

6 9

10 12

11 19

15 26 1

13 39 4

25 47 5

19 70 12

29 89 17

33 115 28

42 148 41

39 189 69

62 235 88

55 294 141

81 362 183 1

Row n = 8 counts the following partitions:

(8) (332)

(44) (422)

(53) (611)

(62) (3221)

(71) (4211)

(431) (5111)

(521) (22211)

(2222) (32111)

(3311) (41111)

(11111111) (221111)

(311111)

(2111111)

MATHEMATICA

DeleteCases[Table[Length[Select[IntegerPartitions[n], Length[Union[Length/@Split[#]]]==k&]], {n, 20}, {k, n}], 0, 2]

CROSSREFS

Row lengths are A056556. Row sums are A000041. Column k = 1 is A047966. Column k = 2 is A325243.

Cf. A008284, A062770, A071625, A098859, A116608, A127002, A183558, A243978, A244515, A325244, A325268.

Sequence in context: A110630 A343321 A238883 * A257053 A129717 A317088

Adjacent sequences: A325239 A325240 A325241 * A325243 A325244 A325245

KEYWORD

nonn,tabf

AUTHOR

Gus Wiseman, Apr 15 2019

STATUS

approved

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Last modified March 1 12:21 EST 2023. Contains 360770 sequences. (Running on oeis4.)