login
A351864
Numerator of zeta({6}_n)/Pi^(6n).
1
1, 1, 4, 2, 4, 1, 4, 4, 4, 4, 16, 2, 4, 2, 8, 8, 4, 4, 16, 8, 16, 1, 4, 4, 4, 4, 16, 4, 8, 4, 16, 16, 4, 4, 16, 8, 16, 4, 16, 16, 16, 16, 64, 2, 4, 2, 8, 8, 4, 4, 16, 8, 16, 2, 8, 8, 8, 8, 32, 8, 16, 8, 32, 32, 4, 4, 16, 8, 16, 4, 16
OFFSET
0,3
COMMENTS
({6}_n) is standard notation for multiple zeta values. It represents (6, ..., 6) where the multiplicity of 6 is n.
LINKS
J. M. Borwein, D. M. Bradley, and D. J. Broadhurst, Evaluations of k-fold Euler/Zagier sums: a compendium of results for arbitrary k, arXiv:hep-th/9611004, 1996.
Roudy El Haddad, Multiple Sums and Partition Identities, arXiv:2102.00821 [math.CO], 2021.
Roudy El Haddad, A generalization of multiple zeta value. Part 2: Multiple sums. Notes on Number Theory and Discrete Mathematics, 28(2), 2022, 200-233, DOI: 10.7546/nntdm.2022.28.2.200-233.
FORMULA
a(n) = numerator(6*2^(6*n)/(6*n + 3)!).
a(n) = 2^(A000120(3*n + 1) - 1).
a(n) = 2^A240883(n).
MATHEMATICA
a[n_] := Numerator[6*2^(6*n)/(6*n + 3)!]; Array[a, 71, 0]
PROG
(PARI) a(n) = 1 << (hammingweight(3*n+1) - 1);
CROSSREFS
Cf. A351806 (denominators).
Sequence in context: A135513 A176895 A335261 * A256789 A226577 A179950
KEYWORD
nonn,easy,frac
AUTHOR
Roudy El Haddad, Feb 22 2022
STATUS
approved