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A123181 Numbers such that (-1)Sigma(m)*UnitarySigma(m)= k*UnitaryPhi(m)*m for some integer k. 1
6, 312, 495, 990, 20520, 23664, 64416, 13063050 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

R. J. Mathar did an exhaustive search up to 74000000. Kohmoto found one more term. 2^8*3*11*43*257*509 But between 7.4*10^7 and it, many terms be missing.

CROSSREFS

Cf. A123182.

Sequence in context: A159494 A104003 A015103 * A074656 A204462 A135397

Adjacent sequences:  A123178 A123179 A123180 * A123182 A123183 A123184

KEYWORD

nonn

AUTHOR

Yasutoshi Kohmoto zbi74583(AT)boat.zero.ad.jp,Oct 03 2006

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Last modified February 15 21:56 EST 2012. Contains 205860 sequences.