login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A359072
Denominators of the partial sums of the reciprocals of the maximal exponent in prime factorization of the positive integers (A051903).
2
1, 1, 2, 2, 2, 2, 6, 3, 3, 3, 6, 6, 6, 6, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 4, 4, 4, 4, 4, 20, 20, 20, 20, 20, 20, 20, 20, 60, 60, 60, 60, 60, 60, 60, 60, 30, 15, 30, 30, 15, 15, 15, 15, 5, 5, 5, 5, 10, 10, 10, 5, 30, 30, 30, 30, 15, 15, 15, 15, 5, 5
OFFSET
2,3
LINKS
Wolfgang Schwarz and Jürgen Spilker, A remark on some special arithmetical functions, in: E. Laurincikas, E. Manstavicius and V. Stakenas (eds.), Analytic and Probabilistic Methods in Number Theory, Proceedings of the Second International Conference in Honour of J. Kubilius, Palanga, Lithuania, 23-27 September 1996, New Trends in Probability and Statistics, Vol. 4, VSP BV & TEV Ltd. (1997), pp. 221-245.
D. Suryanarayana and R. Chandra Rao, On the maximum and minimum exponents in factoring integers, Archiv der Mathematik, Vol. 28, No. 1 (1977), pp. 261-269.
FORMULA
a(n) = denominator(Sum_{k=2..n} 1/A051903(k)).
MATHEMATICA
f[n_] := Max[FactorInteger[n][[;; , 2]]]; f[1] = 0; Denominator[Accumulate[Table[1/f[n], {n, 2, 100}]]]
CROSSREFS
Cf. A051903, A129132, A359071 (numerators).
Sequence in context: A293221 A334512 A096625 * A263455 A283677 A355192
KEYWORD
nonn,frac
AUTHOR
Amiram Eldar, Dec 15 2022
STATUS
approved