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.

A258652 Sum of the k-th arithmetic derivative of n-k for k=0..n.

Original entry on oeis.org

0, 1, 2, 4, 5, 9, 11, 16, 14, 25, 36, 59, 99, 209, 419, 860, 1730, 3862, 9464, 21868, 74371, 244648, 727345, 3098351, 13469007, 56269849, 281642632, 1406177909, 9597415332, 58891421656, 411673964638, 3406742649805, 24202753250241, 176482943622608
Offset: 0

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Author

Alois P. Heinz, Jun 06 2015

Keywords

Crossrefs

Antidiagonal sums of A258651.
Cf. A003415.

Programs

  • Maple
    d:= n-> n*add(i[2]/i[1], i=ifactors(n)[2]):
    A:= proc(n, k) option remember; `if`(k=0, n, d(A(n, k-1))) end:
    a:= proc(n) option remember; add(A(h, n-h), h=0..n) end:
    seq(a(n), n=0..40);
  • Mathematica
    d[n_ /; n>1] := n*Sum[i[[2]]/i[[1]], {i, FactorInteger[n]}]; d[_] = 0;
    A[n_, k_] := A[n, k] = If[k == 0, n, d[A[n, k-1]]];
    a[n_] := a[n] = Sum[A[h, n-h], {h, 0, n}];
    Table[a[n], {n, 0, 40}] (* Jean-François Alcover, Jun 01 2018, from Maple *)

Formula

a(n) = Sum_{k=0..n} A258651(n-k,k).