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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A035479 (-1)sigma sequence: a(n) = (-1)sigma(a(n-1)), where if (-1)sigma(k) = A049060(k) and a(1) = 624.

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%I A035479 #12 Aug 26 2022 07:29:31
%S A035479 624,696,728,936,1716,1200,1682,869,780,480,488,780,480,488,780,480,
%T A035479 488,780,480,488,780,480,488,780,480,488,780,480,488,780,480,488,780,
%U A035479 480,488,780,480,488,780,480,488,780,480,488,780,480,488,780,480,488,780,480
%N A035479 (-1)sigma sequence: a(n) = (-1)sigma(a(n-1)), where if (-1)sigma(k) = A049060(k) and a(1) = 624.
%C A035479 This sequence becomes a cycle of period 3: 780, 480, 488. It is called a (-1)sigma sociable group of order 3.
%e A035479 Factorizations: 2^4*3*13, 2^3*3*29, 2^3*7*13, 2^3*3^2*13, 2^2*3*11*13,  2^4*3*5^2, 2*29^2, 11*79, 2^2*3*5*13, 2^5*3*5, 2^3*61.
%t A035479 f[p_, e_] := (p^(e + 1) - 1)/(p - 1) - 2; s[n_] := Times @@ f @@@ FactorInteger[n]; s[1] = 1; NestList[s, 624, 50] (* _Amiram Eldar_, Aug 26 2022 *)
%Y A035479 Cf. A049060.
%K A035479 nonn
%O A035479 1,1
%A A035479 _Yasutoshi Kohmoto_
%E A035479 Offset corrected by _Amiram Eldar_, Aug 26 2022