A369867 - OEIS

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A369867

a(n) = n * Sum_{p|n, p prime} prime(n/p) / p.

0, 2, 2, 6, 2, 21, 2, 28, 15, 61, 2, 106, 2, 125, 70, 152, 2, 285, 2, 318, 134, 347, 2, 596, 55, 539, 207, 630, 2, 1073, 2, 848, 356, 1009, 174, 1542, 2, 1279, 548, 1572, 2, 2213, 2, 1766, 912, 1915, 2, 2984, 119, 2715, 1018, 2654, 2, 3879, 396, 3148, 1288, 3167

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Table of n, a(n) for n=1..58.

FORMULA

From Wesley Ivan Hurt, May 10 2024: (Start)

a(p^k) = p^(k-1) * prime(p^(k-1)) for primes p and k >= 1.

a(A246655(n)) = A033286(A003557(A246655(n))). (End)

MATHEMATICA

Table[n*DivisorSum[n, Prime[n/#]/# &, PrimeQ[#] &], {n, 60}]

PROG