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A049225 Values of totient function applied to squarefree numbers; or numbers of form Product (p_i-1) where p_i are distinct primes. 0
1, 2, 4, 6, 8, 10, 12, 16, 18, 20, 22, 24, 28, 30, 32, 36, 40, 42, 44, 46, 48, 52, 56, 58, 60, 64, 66, 70, 72, 78, 80, 82, 84, 88, 92, 96, 100, 102, 104, 106, 108, 112, 116, 120, 126, 128, 130, 132, 136, 138, 140, 144, 148, 150, 156, 160, 162, 164, 166, 168, 172, 176 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

FORMULA

EulerPhi[ x ] when Abs[ mu[ x ] ]=1, then the sequence is ordered by magnitude.

EXAMPLE

8,120,48 are here as totient functions of squarefree numbers 15,143,210. 54 and 110,294,342 are missing since not EulerPhi value of any squarefree numbers.

CROSSREFS

Terms of A049200 after ordering and omitting multiple occurrences.

Cf. A000010, A005117, A013929, A002174, A002202, A049200.

Sequence in context: A049445 A002174 A002202 * A076450 A097379 A114871

Adjacent sequences:  A049222 A049223 A049224 * A049226 A049227 A049228

KEYWORD

nonn

AUTHOR

Labos E. (labos(AT)ana.sote.hu)

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Last modified February 14 20:38 EST 2012. Contains 205663 sequences.