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A325197 Heinz numbers of integer partitions such that the difference between the length of the minimal triangular partition containing and the maximal triangular partition contained in the Young diagram is 2. 8
5, 8, 14, 21, 24, 25, 27, 28, 35, 36, 40, 54, 56, 66, 98, 99, 110, 120, 125, 132, 135, 147, 154, 165, 168, 175, 180, 189, 196, 198, 200, 220, 225, 231, 245, 250, 252, 264, 270, 275, 280, 297, 300, 308, 375, 378, 385, 390, 392, 396, 440, 450, 500, 546, 585, 594 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
The enumeration of these partitions by sum is given by A325199.
LINKS
EXAMPLE
The sequence of terms together with their prime indices begins:
5: {3}
8: {1,1,1}
14: {1,4}
21: {2,4}
24: {1,1,1,2}
25: {3,3}
27: {2,2,2}
28: {1,1,4}
35: {3,4}
36: {1,1,2,2}
40: {1,1,1,3}
54: {1,2,2,2}
56: {1,1,1,4}
66: {1,2,5}
98: {1,4,4}
99: {2,2,5}
110: {1,3,5}
120: {1,1,1,2,3}
125: {3,3,3}
132: {1,1,2,5}
MATHEMATICA
primeptn[n_]:=If[n==1, {}, Reverse[Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]]];
otb[ptn_]:=Min@@MapIndexed[#1+#2[[1]]-1&, Append[ptn, 0]];
otbmax[ptn_]:=Max@@MapIndexed[#1+#2[[1]]-1&, Append[ptn, 0]];
Select[Range[1000], otbmax[primeptn[#]]-otb[primeptn[#]]==2&]
CROSSREFS
Sequence in context: A314521 A314522 A314523 * A314524 A357359 A314525
KEYWORD
nonn
AUTHOR
Gus Wiseman, Apr 11 2019
STATUS
approved

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Last modified May 13 02:14 EDT 2024. Contains 372497 sequences. (Running on oeis4.)