A104357 - OEIS

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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

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,3

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..640

R. Zumkeller, Products of largest prime factors of numbers <= n

FORMULA

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

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 *)

CROSSREFS