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Revision History for A326018 (Underlined text is an addition; strikethrough text is a deletion.)

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A326018 Heinz numbers of knapsack partitions such that no addition of one part up to the maximum is knapsack.
(history; published version)
#4 by Susanna Cuyler at Tue Jun 04 08:36:18 EDT 2019
STATUS

proposed

approved

#3 by Gus Wiseman at Mon Jun 03 23:35:18 EDT 2019
STATUS

editing

proposed

#2 by Gus Wiseman at Mon Jun 03 05:38:44 EDT 2019
NAME

allocatedHeinz numbers of knapsack partitions such that no addition of one part up to the formaximum Gusis Wisemanknapsack.

DATA

1925, 12155, 20995, 23375, 37145

OFFSET

1,1

COMMENTS

The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k).

An integer partition is knapsack if every submultiset has a different sum.

The enumeration of these partitions by sum is given by A326016.

EXAMPLE

The sequence of terms together with their prime indices begins:

1925: {3,3,4,5}

12155: {3,5,6,7}

20995: {3,6,7,8}

23375: {3,3,3,5,7}

37145: {3,7,8,9}

MATHEMATICA

ksQ[y_]:=UnsameQ@@Total/@Union[Subsets[y]];

Select[Range[2, 200], With[{phm=If[#==1, {}, Flatten[Cases[FactorInteger[#], {p_, k_}:>Table[PrimePi[p], {k}]]]]}, ksQ[phm]&&Select[Table[Sort[Append[phm, i]], {i, Max@@phm}], ksQ]=={}]&]

CROSSREFS

Cf. A002033, A108917, A275972, A299702, A299729, A304793.

Cf. A325780, A325782, A325857, A325862, A325878, A325880, A326015, A326016.

KEYWORD

allocated

nonn,more

AUTHOR

Gus Wiseman, Jun 03 2019

STATUS

approved

editing

#1 by Gus Wiseman at Sat Jun 01 18:41:30 EDT 2019
NAME

allocated for Gus Wiseman

KEYWORD

allocated

STATUS

approved

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Last modified August 30 03:24 EDT 2024. Contains 375523 sequences. (Running on oeis4.)