OFFSET
1,1
LINKS
N. J. A. Sloane, Table of n, a(n) for n = 1..100
D. Applegate, M. LeBrun and N. J. A. Sloane, Dismal Arithmetic [Note: we have now changed the name from "dismal arithmetic" to "lunar arithmetic" - the old name was too depressing]
EXAMPLE
1 has 9 divisors: 1,2,3,4,5,6,7,8,9, so a(1)=9. 11 has 90 divisors, 1 through 9 and the numbers 11 through 99 that do not end in 0, so a(2)=90.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, Mar 01 2011
STATUS
approved