Let S(n)=sigma(n)/3. Numbers k such that S(S(k))=k, 1/3-sociable number of order 1 or 2.

A113546

Let S(n)=sigma(n)/3. Numbers k such that S(S(k))=k, 1/3-sociable number of order 1 or 2.

Terms

    a(0) =120a(1) =672a(2) =7680a(3) =8184a(4) =523776a(5) =1100190a(6) =1124352a(7) =14913024a(8) =16149760a(9) =459818240a(10) =775898880a(11) =874897408a(12) =1476304896a(13) =51001180160

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