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A231545 Numbers n such that n = sigma(n) - sigma(n-1). 3
2, 6, 8586, 16120, 29886160 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
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.
Numbers n such that A163553(n-1) = 0.
LINKS
FORMULA
a(n) = A067816(n) + 1.
EXAMPLE
6 is in sequence because antisigma(6) = antisigma(5) = 9.
CROSSREFS
Cf. A067816, A024816 (antisigma(n)), A231546 (numbers n such that sigma(n) = sigma(n-1)).
Sequence in context: A357193 A355556 A162146 * A055698 A121167 A115658
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Nov 11 2013
STATUS
approved

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Last modified May 23 16:36 EDT 2024. Contains 372765 sequences. (Running on oeis4.)