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A369868
a(n) = Sum_{p|n, p prime} n^pi(n/p).
1
0, 1, 1, 4, 1, 42, 1, 64, 81, 1010, 1, 1872, 1, 38430, 3600, 65536, 1, 110808, 1, 160400, 194922, 5153654, 1, 8294400, 15625, 308915802, 531441, 481891088, 1, 729837000, 1, 1073741824, 39136482, 52523350178, 1543500, 78424630272, 1, 4347792138534, 3518745282
OFFSET
1,4
FORMULA
a(p^k) = p^(k*pi(p^(k-1))), for p prime and k >= 1. - Wesley Ivan Hurt, Jun 26 2024
MATHEMATICA
Table[DivisorSum[n, n^PrimePi[n/#] &, PrimeQ[#] &], {n, 60}]
CROSSREFS
Sequence in context: A298495 A373827 A193962 * A302441 A373459 A269906
KEYWORD
nonn,easy
AUTHOR
Wesley Ivan Hurt, Feb 03 2024
STATUS
approved