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 A123181 Numbers such that (-1)Sigma(m)*UnitarySigma(m)= k*UnitaryPhi(m)*m for some integer k. 1
 1, 6, 312, 495, 990, 20520, 23664, 64416, 13063050 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS R. J. Mathar did an exhaustive search up to 74000000. Kohmoto found one more term, 2^8*3*11*43*257*509 with k=3, but between 7.4*10^7 and this term, many terms may be missing. LINKS MAPLE isA123181 := proc(m) A047994(m) ; modp(A049060(m)*A034448(m), %*m) = 0 ; end proc: for m from 1 do if isA123181(m) then printf("%a, \n", m) ; end if; end do: # R. J. Mathar, Sep 04 2018 CROSSREFS Cf. A123182, A049060, A034448, A047994. Sequence in context: A280215 A015103 A282373 * A281932 A074656 A233108 Adjacent sequences: A123178 A123179 A123180 * A123182 A123183 A123184 KEYWORD nonn,more AUTHOR Yasutoshi Kohmoto, Oct 03 2006 EXTENSIONS 1 preprended by R. J. Mathar, Sep 04 2018 STATUS approved

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Last modified December 7 13:02 EST 2022. Contains 358656 sequences. (Running on oeis4.)