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.
Numbers n such that antisigma(n) > antisigma(n-1) = A231711.
Numbers n such that antisigma(n) = antisigma(n-1) = A231545.
Does this sequence have a density? - Charles R Greathouse IV, Jul 14 2024
LINKS
Jaroslav Krizek, Table of n, a(n) for n = 1..1000
EXAMPLE
12 is in sequence because antisigma(12) = 50 < antisigma(11) = 54.
MATHEMATICA
Select[Range[350], #<(DivisorSigma[1, #]-DivisorSigma[1, #-1])&] (* Harvey P. Dale, May 26 2016 *)
PROG
(PARI) is(n)=n<sigma(n)-sigma(n-1) \\ Charles R Greathouse IV, Jul 14 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Nov 12 2013
STATUS
approved