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A217842 Product of the numbers p such that phi(p) = n, where phi is Euler's totient function. 2
2, 72, 1, 4800, 1, 15876, 1, 3456000, 1, 242, 1, 300500928, 1, 1, 1, 2130739200, 1, 1052676, 1, 119790000, 1, 1058, 1, 531598161669120000, 1, 1, 1, 1682, 1, 1922, 1, 20864198246400, 1, 1, 1, 1159208596538496, 1, 1, 1, 265804426800000000, 1, 17757796, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
It appears that all terms greater than 1 are distinct. This is true for all n <= 10^6.
LINKS
D. Bressoud, CNT.m Computational Number Theory Mathematica package.
MATHEMATICA
Needs["CNT`"]; Table[Times @@ PhiInverse[n], {n, 100}]
CROSSREFS
Cf. A002181 (smallest inverse), A006511 (largest inverse), A215240 (sum of inverses).
Cf. A032447 (inverse of phi).
Sequence in context: A055030 A361688 A185120 * A053318 A272757 A187707
KEYWORD
nonn
AUTHOR
T. D. Noe, Oct 12 2012
STATUS
approved

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Last modified April 19 18:05 EDT 2024. Contains 371798 sequences. (Running on oeis4.)