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 A192275 Super anti-perfect numbers. 0
 7, 167, 507, 543, 3433, 6707, 9615, 15690, 87667, 1023971, 2054435, 5871045, 9150387, 14146891, 63538839, 169623015 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Like A019279 but using anti-divisors. sigma*^2(n)=sigma*(sigma*(n))=2n, where sigma*(n) is the sum of the anti-divisors of n. LINKS MAPLE for n from 1 do         if A066417(A066417(n)) = 2*n then                 print(n);         end if; end do: # R. J. Mathar, Oct 02 2011 CROSSREFS Cf. A019279, A066417. Sequence in context: A012504 A012689 A098632 * A009807 A220991 A165388 Adjacent sequences:  A192272 A192273 A192274 * A192276 A192277 A192278 KEYWORD nonn,more AUTHOR Paolo P. Lava, Jun 28 2011 EXTENSIONS a(9)-a(16) from Donovan Johnson, Sep 22 2011 STATUS approved

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Last modified January 17 07:32 EST 2021. Contains 340214 sequences. (Running on oeis4.)