A104357 a(n) = A104350(n) - 1.

0, 1, 5, 11, 59, 179, 1259, 2519, 7559, 37799, 415799, 1247399, 16216199, 113513399, 567566999, 1135133999, 19297277999, 57891833999, 1099944845999, 5499724229999, 38498069609999, 423478765709999, 9740011611329999

Offset: 1

Author

Reinhard Zumkeller, Mar 06 2005

Keywords

• nonn

Links

• G. C. Greubel, Table of n, a(n) for n = 1..640
• R. Zumkeller, Products of largest prime factors of numbers <= n

Crossrefs

Cf. A104358, A104359, A104360, A104361, A104362, A104363, A104365, A033312, A057588.

Programs

Mathematica

A104350[n_] := Product[FactorInteger[k][[-1, 1]], {k, 1, n}]; Table[A104350[n] - 1, {n, 1, 50}] (* G. C. Greubel, May 09 2017 *)
FoldList[Times,Table[FactorInteger[n][[-1,1]],{n,30}]]-1 (* Harvey P. Dale, May 28 2018 *)

Formula

a(n) = (a(n-1) + 1) * A006530(n) - 1 for n>1, a(1) = 0;