A316265 FDH numbers of strict integer partitions with prime parts.
1, 3, 4, 7, 11, 12, 19, 21, 25, 28, 33, 41, 44, 47, 57, 61, 75, 76, 77, 83, 84, 97, 100, 121, 123, 132, 133, 139, 141, 151, 164, 169, 175, 183, 188, 197, 209, 228, 231, 233, 241, 244, 249, 271, 275, 287, 289, 291, 300, 307, 308, 329, 332, 347, 361, 363, 388
Offset: 1
Keywords
Examples
Sequence of strict integer partitions with prime parts, preceded by their FDH numbers, begins: 1: () 3: (2) 4: (3) 7: (5) 11: (7) 12: (3,2) 19: (11) 21: (5,2) 25: (13) 28: (5,3) 33: (7,2) 41: (17) 44: (7,3) 47: (19) 57: (11,2) 61: (23) 75: (13,2) 76: (11,3) 77: (7,5) 83: (29) 84: (5,3,2)
Crossrefs
Programs
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Mathematica
nn=100; 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)]]]]]; FDprimeList=Array[FDfactor,nn,1,Union];FDrules=MapIndexed[(#1->#2[[1]])&,FDprimeList]; Select[Range[nn],And@@PrimeQ/@(FDfactor[#]/.FDrules)&]
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