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A030163 2*uphi(x)=x, where the unitary phi function (A047994) is defined by if x=p1^r1*p2^r2*p3^r3*... then uphi(x)=(p1^r1-1)(p2^r2-1)(p3^r3-1)... 3
2, 12, 168, 240, 14880, 65280, 7608944640, 4294901760, 1125874137169920, 18446744069414584320 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..9.

CROSSREFS

Sequence in context: A201007 A226058 A120958 * A255163 A052728 A052729

Adjacent sequences:  A030160 A030161 A030162 * A030164 A030165 A030166

KEYWORD

nonn

AUTHOR

Yasutoshi Kohmoto

STATUS

approved

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Last modified November 17 19:40 EST 2017. Contains 294834 sequences.