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A317246 Heinz numbers of supernormal integer partitions. 20
1, 2, 4, 6, 8, 12, 16, 18, 30, 32, 60, 64, 90, 128, 150, 180, 210, 256, 300, 360, 450, 512, 540, 600, 1024, 1350, 1500, 2048, 2250, 2310, 2520, 3780, 4096, 4200, 5880, 8192, 9450, 10500, 12600, 13230, 15750, 16384, 17640, 18900, 20580, 26460, 29400, 30030 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
An integer partition is supernormal if either (1) it is of the form 1^n for some n >= 0, or (2a) it spans an initial interval of positive integers, and (2b) its multiplicities, sorted in weakly decreasing order, are themselves a supernormal integer partition.
LINKS
EXAMPLE
Sequence of supernormal integer partitions begins: (), (1), (11), (21), (111), (211), (1111), (221), (321), (11111), (3211), (111111), (3221), (1111111), (3321), (32211), (4321).
MATHEMATICA
primeMS[n_]:=If[n==1, {}, Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]];
supnrm[q_]:=Or[q=={}||Union[q]=={1}, And[Union[q]==Range[Max[q]], supnrm[Sort[Length/@Split[q], Greater]]]];
Select[Range[10000], supnrm[primeMS[#]]&]
CROSSREFS
Sequence in context: A007694 A322492 A332276 * A279686 A219653 A050622
KEYWORD
nonn
AUTHOR
Gus Wiseman, Jul 24 2018
STATUS
approved

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Last modified June 21 01:33 EDT 2024. Contains 373535 sequences. (Running on oeis4.)