cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-2 of 2 results.

A230284 Denominators to Dirichlet inverse of Euler totient based version of series expansion for x/LambertW(x).

Original entry on oeis.org

1, 1, 2, 3, 8, 15, 144, 35, 5760, 315, 5600, 693, 43545600, 1001, 6706022400, 6435, 14014, 109395, 376610217984000, 46189, 128047474114560000, 323323, 2540395, 2028117, 26976017466662584320000, 96577, 3241475864250624, 35102025, 2126818694000, 5386025
Offset: 1

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Author

Mats Granvik, Oct 15 2013

Keywords

Crossrefs

Cf. A191898, A177885, A230283 (numerators).
Similar to but strictly different from A264235.

Programs

  • Mathematica
    Clear[nn, n, k, s, x]; nn = 22; Denominator[CoefficientList[1 + Integrate[1 + Expand[Sum[Exp[Limit[Zeta[s]*Sum[(If[n == 1, 0, Table[DivisorSum[m, # MoebiusMu[#] &], {m, nn}][[GCD[n, k]]]])/(k)^(s - 1), {k, 1, n}], s -> 1]]*(-x)^n, {n, 1, nn}]], x], x]]

A276048 Sequence associated with the functional equation of the Riemann zeta zero spectrum (see formulas).

Original entry on oeis.org

0, 2, 9, 2, 625, 1, 117649, 2, 9, 1, 25937424601, 1, 23298085122481, 1, 1, 2, 48661191875666868481, 1, 104127350297911241532841, 1, 1, 1, 907846434775996175406740561329, 1, 625, 1, 9, 1, 88540901833145211536614766025207452637361, 1
Offset: 1

Views

Author

Mats Granvik, Aug 17 2016

Keywords

Comments

The functional equation formula in the answer by Peter Humphries is for the Dirichlet eta function and corresponds to the second term in this sequence. This sequence corresponds to zeta function products over all the divisors.

Crossrefs

Programs

  • Mathematica
    Clear[s]; -Table[Limit[Zeta[s]*Total[MoebiusMu[Divisors[n]]*Divisors[n]^(1 - (s))]*Total[MoebiusMu[Divisors[n]]*Divisors[n]^(s)], s -> 1], {n, 1, 30}]; Exp[%]

Formula

a(n) = exp(lim_{s->1} zeta(s)*Sum_{d|n} mu(d)*d^(1 - s)*Sum_{d|n} mu(d)*d^(s)).
a(n) = A014963(n)^(A014963(n)-1), n > 1.
a(n) = A014963(n)^(-A120112(n)), n > 1.
a(prime(n)) = A000169(prime(n)).
Showing 1-2 of 2 results.