A327389 - OEIS

A327389

Maximum divisor of n that is prime or whose prime indices are pairwise coprime.

1, 2, 3, 4, 5, 6, 7, 8, 3, 10, 11, 12, 13, 14, 15, 16, 17, 6, 19, 20, 7, 22, 23, 24, 5, 26, 3, 28, 29, 30, 31, 32, 33, 34, 35, 12, 37, 38, 13, 40, 41, 14, 43, 44, 15, 46, 47, 48, 7, 10, 51, 52, 53, 6, 55, 56, 19, 58, 59, 60, 61, 62, 7, 64, 13, 66, 67, 68, 69

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OFFSET

1,2

COMMENTS

A prime index of n is a number m such that prime(m) divides n. The multiset of prime indices of n is row n of A112798.

LINKS

Table of n, a(n) for n=1..69.

Gus Wiseman, Sequences counting and encoding certain classes of multisets

FORMULA

If n is in A302569, then a(n) = n.

MATHEMATICA

primeMS[n_]:=If[n==1, {}, Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]];