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A319680 a(n) = Product_{d|n} A019565(d)^[moebius(n/d) = +1]. 2
2, 3, 6, 5, 10, 30, 30, 7, 14, 42, 42, 105, 70, 210, 420, 11, 22, 198, 66, 165, 220, 330, 330, 385, 154, 462, 462, 1155, 770, 207900, 2310, 13, 52, 78, 156, 975, 130, 390, 780, 455, 182, 147420, 546, 1365, 5460, 2730, 2730, 1001, 286, 4290, 1716, 2145, 1430, 30030, 8580, 5005, 4004, 6006, 6006, 7882875, 10010, 30030, 180180, 17, 68 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
FORMULA
a(n) = A019565(n) * A300831(n).
PROG
(PARI)
A019565(n) = {my(j, v); factorback(Mat(vector(if(n, #n=vecextract(binary(n), "-1..1")), j, [prime(j), n[j]])~))}; \\ From A019565
A319680(n) = { my(m=1); fordiv(n, d, if((1==moebius(n/d)), m *= A019565(d))); m; };
CROSSREFS
Cf. A019565, A300831, A319681 (rgs-transform).
Sequence in context: A309840 A340316 A274608 * A350337 A133477 A303695
KEYWORD
nonn
AUTHOR
Antti Karttunen, Sep 29 2018
STATUS
approved

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Last modified March 28 08:12 EDT 2024. Contains 371236 sequences. (Running on oeis4.)