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A369913
a(n) = Sum_{p|n, p prime} n^sopf(n/p).
1
0, 1, 1, 16, 1, 252, 1, 64, 729, 100100, 1, 248976, 1, 105413700, 762750, 256, 1, 1895400, 1, 1280000400, 1801097802, 584318301411812, 1, 7963200, 9765625, 2481152873203737252, 19683, 10578455954192, 1, 677994300000, 1, 1024, 50542106513762754
OFFSET
1,4
MATHEMATICA
a[n_] := Sum[p, {p, Select[Divisors[n], PrimeQ]}]; Table[DivisorSum[n, n^a[n/#] &, PrimeQ[#] &], {n, 40}]
CROSSREFS
Sequence in context: A351244 A105671 A145828 * A371081 A223518 A095876
KEYWORD
nonn,easy
AUTHOR
Wesley Ivan Hurt, Feb 05 2024
STATUS
approved