A083718 (greatest prime <= n) + (greatest prime factor of n).

2, 4, 6, 5, 10, 8, 14, 9, 10, 12, 22, 14, 26, 20, 18, 15, 34, 20, 38, 24, 26, 30, 46, 26, 28, 36, 26, 30, 58, 34, 62, 33, 42, 48, 38, 34, 74, 56, 50, 42, 82, 48, 86, 54, 48, 66, 94, 50, 54, 52, 64, 60, 106, 56, 64, 60, 72, 82, 118, 64, 122, 92, 68, 63, 74, 72, 134, 84, 90, 74

Offset

1,1

Comments

a(n) = A007917(n) + A006530(n).

Links

Table of n, a(n) for n=1..70.

Mathematica

Join[{2}, Table[If[PrimeQ[n], n, NextPrime[n, -1]]+FactorInteger[n][[-1, 1]], {n, 2, 70}]] (* Harvey P. Dale, Aug 11 2016 *)

Crossrefs

Cf. A083714, A083715, A083716, A083717.

Sequence in context: A365060 A376548 A365059 * A319804 A055948 A071083

Adjacent sequences: A083715 A083716 A083717 * A083719 A083720 A083721

Keyword

nonn

Author

Reinhard Zumkeller, May 04 2003

Status

approved