login
A227981
Numbers n such that sigma(n-1) - sigma(n+1) < sigma(n); where sigma(n) = A000203(n) = sum of the divisors of n.
2
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 62, 63, 64, 65, 66, 67, 68, 69, 70
OFFSET
1,2
COMMENTS
There is no number n < 100000 such that sigma(n-1) - sigma(n+1) = sigma(n).
Complement of A227980.
LINKS
EXAMPLE
Number 60 is in the sequence because sigma(59) - sigma(61) = 60 - 62 = -2 < sigma(60) = 168.
CROSSREFS
Sequence in context: A144972 A166719 A272159 * A085736 A265711 A262065
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Aug 02 2013
STATUS
approved