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A231545 Numbers n such that n = sigma(n) - sigma(n-1). 3

%I

%S 2,6,8586,16120,29886160

%N Numbers n such that n = sigma(n) - sigma(n-1).

%C Also, numbers n such that antisigma(n) = antisigma(n-1), where antisigma(n) = A024816(n) = the sum of the non-divisors of n that are between 1 and n.

%C Numbers n such that A163553(n-1) = 0.

%F a(n) = A067816(n) + 1.

%e 6 is in sequence because antisigma(6) = antisigma(5) = 9.

%Y Cf. A067816, A024816 (antisigma(n)), A231546 (numbers n such that sigma(n) = sigma(n-1)).

%K nonn

%O 1,1

%A _Jaroslav Krizek_, Nov 11 2013

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Last modified August 22 20:42 EDT 2019. Contains 326197 sequences. (Running on oeis4.)