A088388 - OEIS

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A088388

Exponent of the largest prime power factor of n, a(1)=0.

0, 1, 1, 2, 1, 1, 1, 3, 2, 1, 1, 2, 1, 1, 1, 4, 1, 2, 1, 1, 1, 1, 1, 3, 2, 1, 3, 1, 1, 1, 1, 5, 1, 1, 1, 2, 1, 1, 1, 3, 1, 1, 1, 1, 2, 1, 1, 4, 2, 2, 1, 1, 1, 3, 1, 3, 1, 1, 1, 1, 1, 1, 2, 6, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 2, 1, 1, 1, 1, 4, 4, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 5, 1, 2, 1, 2, 1, 1

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OFFSET

1,4

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..65537

FORMULA

A034699(n) = A088387(n)^a(n).

MATHEMATICA

a[n_] := If[n==1, 0, MaximalBy[FactorInteger[n], #[[1]]^#[[2]]&][[1, 2]]];

Array[a, 100] (* Jean-François Alcover, Dec 03 2021 *)

PROG

(PARI) A088388(n) = if(1==n, 0, my(f=factor(n)); isprimepower(vecmax(vector(#f[, 1], i, f[i, 1]^f[i, 2])))); \\ Antti Karttunen, Jul 22 2018