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A143417 Irregular triangle in which row n gives the k such that the reduced totient function psi(k) = A002174(n). 2
1, 2, 3, 4, 6, 8, 12, 24, 5, 10, 15, 16, 20, 30, 40, 48, 60, 80, 120, 240, 7, 9, 14, 18, 21, 28, 36, 42, 56, 63, 72, 84, 126, 168, 252, 504, 32, 96, 160, 480, 11, 22, 33, 44, 66, 88, 132, 264, 13, 26, 35, 39, 45, 52, 65, 70, 78, 90, 91, 104, 105, 112, 117, 130, 140, 144, 156 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Row n consists of the divisors of A143407(n) that are not divisors of A143407(r) for r<n. The length of row n is A143408(n).
LINKS
EXAMPLE
1,2; 3,4,6,8,12,24; 5,10,15,16,20,30,40,48,60,80,120,240
CROSSREFS
Cf. A002322 (reduced totient function).
Sequence in context: A135108 A018515 A018253 * A018597 A018623 A018703
KEYWORD
nonn,tabf,look
AUTHOR
T. D. Noe, Aug 13 2008
STATUS
approved

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Last modified April 24 20:06 EDT 2024. Contains 371963 sequences. (Running on oeis4.)