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A335079 Row sums of A335078. 3
1, 1, 2, 1, 2, 1, 3, 2, 2, 1, 4, 1, 2, 2, 5, 1, 4, 1, 4, 2, 2, 1, 8, 2, 2, 3, 4, 1, 6, 1, 7, 2, 2, 2, 11, 1, 2, 2, 8, 1, 6, 1, 4, 4, 2, 1, 16, 2, 4, 2, 4, 1, 8, 2, 8, 2, 2, 1, 16, 1, 2, 4, 13, 2, 6, 1, 4, 2, 6, 1, 24, 1, 2, 4, 4, 2, 6, 1, 16, 5, 2, 1, 16, 2, 2, 2, 8, 1, 16 (list; graph; refs; listen; history; text; internal format)
OFFSET
2,3
LINKS
MATHEMATICA
tau[n_, k_]:=If[n==1, 1, Product[Binomial[Extract[Extract[FactorInteger[n], i], 2]+k, k], {i, 1, Length[FactorInteger[n]]}]]; (* A334997 *)
Nd[n_, m_]:=Sum[(-1)^k*Binomial[m, k]*tau[n, m-k-1], {k, 0, m-1}]; (* A334996 *)
T[n_, k_]:=1/k*DivisorSum[k, EulerPhi[#]*Nd[n^(1/#), k/#]&, IntegerQ[n^(1/#)]&]; (* A335078 *)
Table[Sum[T[n, m], {m, 1, PrimeOmega[n]}], {n, 2, 90}]
PROG
(PARI) TT(n, k) = if (k==0, 1, sumdiv(n, d, TT(d, k-1))); \\ A334996
U(n, m) = sum(k=0, m-1, (-1)^k*binomial(m, k)*TT(n, m-k-1));
T(n, k) = my(p); (1/k)*sumdiv(k, d, if (ispower(n, d, &p), eulerphi(d)*U(p, k/d)));
row(n) = vector(bigomega(n), k, T(n, k)); \\ A335078
a(n) = vecsum(row(n)); \\ Michel Marcus, May 25 2020
CROSSREFS
Cf. A001222 (Omega function), A334996, A334997, A335078.
Sequence in context: A305254 A252665 A001055 * A337093 A320266 A277692
KEYWORD
nonn
AUTHOR
Stefano Spezia, May 23 2020
STATUS
approved

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Last modified April 23 15:20 EDT 2024. Contains 371916 sequences. (Running on oeis4.)