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.

A078323 Arithmetic derivative of n*rad(n)+1, where rad = A007947 (squarefree kernel).

Original entry on oeis.org

1, 1, 7, 6, 15, 1, 45, 1, 32, 1, 63, 1, 129, 1, 115, 14, 213, 1, 183, 70, 281, 102, 381, 34, 165, 1, 43, 134, 423, 70, 581, 18, 773, 102, 615, 38, 969, 459, 763, 1, 957, 358, 1715, 431, 780, 102, 1847, 34, 524, 170, 1303, 607, 1977, 155, 1725, 162, 3825, 678, 1743
Offset: 1

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Author

Reinhard Zumkeller, Nov 23 2002

Keywords

Crossrefs

Programs

  • Haskell
    a078323 = a003415 . a078310  -- Reinhard Zumkeller, Jul 23 2013
  • Mathematica
    ad[n_] := n * Plus @@ ((Last[#]/First[#]) & /@ FactorInteger[n]); a[n_] := ad[1 + n * Times @@ FactorInteger[n][[;;, 1]]]; Array[a, 100] (* Amiram Eldar, Apr 10 2025 *)

Formula

a(n) = A003415(A078310(n)).