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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.

A307837 a(1) = 1; a(n+1) = Sum_{d|n} lambda(d)*a(d), where lambda = Liouville function (A008836).

Original entry on oeis.org

1, 1, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0, 1, 1, 0, -1, -1, -1, 2, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 1, 2, 1, 0, 1, 0, 2, -1, -2, 3, -3, -2, 1, 1, -1, 2, 3, 3, 2, 3, 3, -2, -3, 4, 4, -3, -3, -3, 4, -3, 4, 4, -3, 4, -5, 6, 6, -6, 8, 9, -9, 10, -8, -6, -7, 8, 7, 6, 5, 6, 7, -6, -8, -7, 6, 7, 9, 9, 5, -4, 2, -1
Offset: 1

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Author

Ilya Gutkovskiy, May 01 2019

Keywords

Crossrefs

Programs

  • Mathematica
    a[n_] := a[n] = Sum[LiouvilleLambda[d] a[d], {d, Divisors[n - 1]}]; a[1] = 1; Table[a[n], {n, 1, 100}]
    a[n_] := a[n] = SeriesCoefficient[x (1 + Sum[LiouvilleLambda[k] a[k] x^k/(1 - x^k), {k, 1, n - 1}]), {x, 0, n}]; Table[a[n], {n, 1, 100}]

Formula

G.f.: x * (1 + Sum_{n>=1} lambda(n)*a(n)*x^n/(1 - x^n)).