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A324107
Fixed points of A324106, where A324106 is a multiplicative function with A324106(p^e) = A005940(p^e).
2
1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 16, 20, 24, 30, 32, 40, 48, 60, 63, 64, 80, 96, 120, 126, 128, 160, 192, 240, 252, 256, 315, 320, 384, 480, 504, 512, 630, 640, 768, 960, 1008, 1024, 1260, 1280, 1536, 1920, 2016, 2048, 2520, 2560, 3072, 3840, 4032, 4096, 5040, 5120, 6144, 7680, 8064, 8192, 10080, 10240, 12288, 15360, 16128, 16384
OFFSET
1,2
COMMENTS
Numbers n such that A324106(n) = n.
EXAMPLE
For n = 63 = 3^2 * 7^1, we find that A005940(9) = 7 and A005940(7) = 9, thus A324106(63) = 7*9 = 63, and 63 is a member of this sequence.
PROG
(PARI)
A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t }; \\ From A005940
A324106(n) = { my(f=factor(n)); prod(i=1, #f~, A005940(f[i, 1]^f[i, 2])); };
isA324107(n) = (n==A324106(n));
for(n=1, 16384, if(isA324107(n), print1(n, ", ")))
CROSSREFS
Cf. A029747 (a subsequence).
Sequence in context: A303704 A067939 A067784 * A018744 A018478 A018350
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 15 2019
STATUS
approved