OFFSET
1,2
COMMENTS
There is no number n < 100000 such that sigma(n-1) - sigma(n+1) = sigma(n).
Complement of A227980.
LINKS
Jaroslav Krizek, Table of n, a(n) for n = 1..2000
EXAMPLE
Number 60 is in the sequence because sigma(59) - sigma(61) = 60 - 62 = -2 < sigma(60) = 168.
CROSSREFS
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Aug 02 2013
STATUS
approved