A325131 - OEIS

A325131

Heinz numbers of integer partitions where the set of distinct parts is disjoint from the set of distinct multiplicities.

1, 3, 4, 5, 7, 8, 11, 13, 15, 16, 17, 19, 21, 23, 25, 27, 29, 31, 32, 33, 35, 37, 39, 41, 43, 47, 49, 51, 53, 55, 57, 59, 61, 64, 65, 67, 69, 71, 73, 77, 79, 81, 83, 85, 87, 89, 91, 93, 95, 97, 100, 101, 103, 105, 107, 109, 111, 113, 115, 119, 121, 123, 127

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OFFSET

1,2

COMMENTS

The enumeration of these partitions by sum is given by A114639.

The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k), so these are numbers where the prime indices are disjoint from the prime exponents.

LINKS

Table of n, a(n) for n=1..63.

EXAMPLE

The sequence of terms together with their prime indices begins:

1: {}

3: {2}

4: {1,1}

5: {3}

7: {4}

8: {1,1,1}

11: {5}

13: {6}

15: {2,3}

16: {1,1,1,1}

17: {7}

19: {8}

21: {2,4}

23: {9}

25: {3,3}

27: {2,2,2}

29: {10}

31: {11}

32: {1,1,1,1,1}

33: {2,5}

MATHEMATICA

Select[Range[100], Intersection[PrimePi/@First/@FactorInteger[#], Last/@FactorInteger[#]]=={}&]

CROSSREFS

Cf. A000720, A001222, A056239, A109298, A112798, A114639, A118914.

Cf. A324571, A325127, A325128, A325129, A325130.

Sequence in context: A285531 A111801 A108372 * A270342 A066542 A003310

Adjacent sequences: A325128 A325129 A325130 * A325132 A325133 A325134

KEYWORD

nonn

AUTHOR

Gus Wiseman, Apr 01 2019

STATUS

approved