A192275 Super anti-perfect numbers.

7, 167, 507, 543, 3433, 6707, 9615, 15690, 87667, 1023971, 2054435, 5871045, 9150387, 14146891, 63538839, 169623015

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

Table of n, a(n) for n=1..16.

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