A349159 Numbers whose sum of prime indices is twice their alternating sum.
1, 12, 63, 66, 112, 190, 255, 325, 408, 434, 468, 609, 805, 832, 931, 946, 1160, 1242, 1353, 1380, 1534, 1539, 1900, 2035, 2067, 2208, 2296, 2387, 2414, 2736, 3055, 3108, 3154, 3330, 3417, 3509, 3913, 4185, 4340, 4503, 4646, 4650, 4664, 4864, 5185, 5684, 5863
Offset: 1
Keywords
Examples
The terms and their prime indices begin: 1: () 12: (2,1,1) 63: (4,2,2) 66: (5,2,1) 112: (4,1,1,1,1) 190: (8,3,1) 255: (7,3,2) 325: (6,3,3) 408: (7,2,1,1,1) 434: (11,4,1) 468: (6,2,2,1,1) 609: (10,4,2) 805: (9,4,3) 832: (6,1,1,1,1,1,1) 931: (8,4,4) 946: (14,5,1) 1160: (10,3,1,1,1)
Crossrefs
Programs
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Mathematica
primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]]; ats[y_]:=Sum[(-1)^(i-1)*y[[i]],{i,Length[y]}]; Select[Range[1000],Total[primeMS[#]]==2*ats[primeMS[#]]&]
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