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A316265 FDH numbers of strict integer partitions with prime parts. 2

%I #6 Jun 29 2018 11:35:18

%S 1,3,4,7,11,12,19,21,25,28,33,41,44,47,57,61,75,76,77,83,84,97,100,

%T 121,123,132,133,139,141,151,164,169,175,183,188,197,209,228,231,233,

%U 241,244,249,271,275,287,289,291,300,307,308,329,332,347,361,363,388

%N FDH numbers of strict integer partitions with prime parts.

%C Let f(n) = A050376(n) be the n-th Fermi-Dirac prime. The FDH number of a strict integer partition (y_1,...,y_k) is f(y_1)*...*f(y_k).

%e Sequence of strict integer partitions with prime parts, preceded by their FDH numbers, begins:

%e 1: ()

%e 3: (2)

%e 4: (3)

%e 7: (5)

%e 11: (7)

%e 12: (3,2)

%e 19: (11)

%e 21: (5,2)

%e 25: (13)

%e 28: (5,3)

%e 33: (7,2)

%e 41: (17)

%e 44: (7,3)

%e 47: (19)

%e 57: (11,2)

%e 61: (23)

%e 75: (13,2)

%e 76: (11,3)

%e 77: (7,5)

%e 83: (29)

%e 84: (5,3,2)

%t nn=100;

%t FDfactor[n_]:=If[n==1,{},Sort[Join@@Cases[FactorInteger[n],{p_,k_}:>Power[p,Cases[Position[IntegerDigits[k,2]//Reverse,1],{m_}->2^(m-1)]]]]];

%t FDprimeList=Array[FDfactor,nn,1,Union];FDrules=MapIndexed[(#1->#2[[1]])&,FDprimeList];

%t Select[Range[nn],And@@PrimeQ/@(FDfactor[#]/.FDrules)&]

%Y Cf. A000586, A045450, A050376, A064547, A213925, A299755, A299757, A316185, A316266, A316267.

%K nonn

%O 1,2

%A _Gus Wiseman_, Jun 28 2018

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