A348617 Numbers whose sum of prime indices is twice their negated alternating sum.
1, 10, 39, 88, 115, 228, 259, 306, 517, 544, 620, 783, 793, 870, 1150, 1204, 1241, 1392, 1656, 1691, 1722, 1845, 2369, 2590, 2596, 2775, 2944, 3038, 3277, 3280, 3339, 3498, 3692, 3996, 4247, 4440, 4935, 5022, 5170, 5226, 5587, 5644, 5875, 5936, 6200, 6321
Offset: 1
Keywords
Examples
The terms and their prime indices begin: 1: () 10: (3,1) 39: (6,2) 88: (5,1,1,1) 115: (9,3) 228: (8,2,1,1) 259: (12,4) 306: (7,2,2,1) 517: (15,5) 544: (7,1,1,1,1,1) 620: (11,3,1,1) 783: (10,2,2,2) 793: (18,6) 870: (10,3,2,1) 1150: (9,3,3,1) 1204: (14,4,1,1) 1241: (21,7) 1392: (10,2,1,1,1,1) 1656: (9,2,2,1,1,1) 1691: (24,8)
Crossrefs
Programs
-
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[#]]&]
Comments