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A303544
Numbers k that divide primepi(k)^prime(k).
1
1, 4, 8, 16, 27, 64, 96, 120, 125, 169, 189, 256, 324, 350, 605, 729, 864, 896, 1008, 1024, 1080, 1116, 1296, 1375, 1444, 2187, 2209, 2268, 2304, 2349, 2401, 2430, 2888, 3087, 3125, 3328, 3645, 3698, 4000, 4096, 4356, 4394, 5184, 6480, 8192, 8464, 10648
OFFSET
1,2
COMMENTS
Except for 1, terms are not squarefree, that is, all terms > 1 form a subsequence of A013929.
LINKS
FORMULA
Numbers k such that the set of prime factors of k is a subset of the set of prime factors of primepi(k).
MATHEMATICA
Select[Range[2^14], PowerMod[PrimePi[#], Prime[#], #] == 0 &] (* Michael De Vlieger, May 14 2018 *)
PROG
(PARI) isok(n) = !(primepi(n)^prime(n) % n); \\ Michel Marcus, May 14 2018
CROSSREFS
Sequence in context: A368985 A334198 A358730 * A273029 A273080 A020193
KEYWORD
nonn
AUTHOR
Chai Wah Wu, Apr 25 2018
STATUS
approved