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A325196 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 1. 9

%I #12 Apr 24 2019 10:11:27

%S 3,4,9,10,12,15,18,20,42,45,50,60,63,70,75,84,90,100,105,126,140,150,

%T 294,315,330,350,420,441,462,490,495,525,550,588,630,660,693,700,735,

%U 770,825,882,924,980,990,1050,1100,1155,1386,1470,1540,1650,2730,3234

%N 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 1.

%C The enumeration of these partitions by sum is given by A325191.

%H Gus Wiseman, <a href="/A325196/a325196.png">Young diagrams for their first 60 terms</a>.

%H FindStat, <a href="http://www.findstat.org/StatisticsDatabase/St000783">St000783: The maximal number of occurrences of a colour in a proper colouring of a Ferrers diagram</a>

%H FindStat, <a href="http://www.findstat.org/StatisticsDatabase/St000384">St000384: The maximal part of the shifted composition of an integer partition</a>.

%e The sequence of terms together with their prime indices begins:

%e 3: {2}

%e 4: {1,1}

%e 9: {2,2}

%e 10: {1,3}

%e 12: {1,1,2}

%e 15: {2,3}

%e 18: {1,2,2}

%e 20: {1,1,3}

%e 42: {1,2,4}

%e 45: {2,2,3}

%e 50: {1,3,3}

%e 60: {1,1,2,3}

%e 63: {2,2,4}

%e 70: {1,3,4}

%e 75: {2,3,3}

%e 84: {1,1,2,4}

%e 90: {1,2,2,3}

%e 100: {1,1,3,3}

%e 105: {2,3,4}

%e 126: {1,2,2,4}

%t primeptn[n_]:=If[n==1,{},Reverse[Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]]];

%t otb[ptn_]:=Min@@MapIndexed[#1+#2[[1]]-1&,Append[ptn,0]];

%t otbmax[ptn_]:=Max@@MapIndexed[#1+#2[[1]]-1&,Append[ptn,0]];

%t Select[Range[1000],otbmax[primeptn[#]]-otb[primeptn[#]]==1&]

%Y Cf. A060687, A065770, A256617, A325166, A325169, A325179, A325181, A325183, A325185, A325188, A325189, A325191, A325195, A325200.

%K nonn

%O 1,1

%A _Gus Wiseman_, Apr 11 2019

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