A086294 Sum of distinct prime factors of 7-smooth numbers.
0, 2, 3, 2, 5, 5, 7, 2, 3, 7, 5, 9, 8, 2, 5, 7, 10, 5, 5, 3, 9, 10, 2, 12, 5, 7, 12, 8, 5, 7, 7, 5, 9, 10, 10, 2, 14, 5, 8, 7, 3, 12, 10, 5, 9, 7, 15, 5, 9, 10, 5, 12, 2, 8, 14, 5, 10, 10, 7, 5, 12, 12, 10, 10, 5, 9, 7, 17, 5, 9, 8, 10, 3, 12, 7, 12, 2, 10, 14, 5, 12, 10, 15, 7, 5, 12, 7
Offset: 1
Keywords
Links
- Amiram Eldar, Table of n, a(n) for n = 1..10000
Programs
-
Mathematica
sumPrimes[1] = 0; sumPrimes[n_] := Plus @@ First[Transpose[FactorInteger[n]]]; sumPrimes/@Select[Range[500], Max[Transpose[FactorInteger[#]][[1]]] <= 7 &] (* Amiram Eldar, Jan 06 2020 *) dpf7[n_]:=Module[{fi=FactorInteger[n][[All,1]]},If[Max[fi]<11,Total[ fi],Nothing]]; Join[{0},Array[dpf7,400,2]] (* Harvey P. Dale, Feb 26 2022 *)