A065967 a(n) = n * Sum_{primes p dividing n} (1 + 1/p).

0, 3, 4, 6, 6, 17, 8, 12, 12, 27, 12, 34, 14, 37, 38, 24, 18, 51, 20, 54, 52, 57, 24, 68, 30, 67, 36, 74, 30, 121, 32, 48, 80, 87, 82, 102, 38, 97, 94, 108, 42, 167, 44, 114, 114, 117, 48, 136, 56, 135, 122, 134, 54, 153, 126, 148, 136, 147, 60, 242

Offset

1,2

Links

Harry J. Smith, Table of n, a(n) for n = 1..1000

Maple

A065967 := proc(n) local i, j, k, t1, t2, t3; t1 := ifactors(n)[2]; t2 := n^1*add((1+1/(t1[i][1])^1), i=1..nops(t1)); end;

Prog

(PARI) a(n) = { my(s=0); foreach(factor(n)[, 1], p, s+=(1 + 1/p)); n*s } \\ Harry J. Smith, Nov 05 2009

Crossrefs

Cf. A065968, A065969, A065970.

Sequence in context: A385135 A220345 A349217 * A345209 A117986 A248738

Adjacent sequences: A065964 A065965 A065966 * A065968 A065969 A065970

Keyword

nonn

Author

N. J. A. Sloane, Dec 09 2001

Status

approved