OFFSET
1,11
COMMENTS
LINKS
Max Alekseyev, Table of n, a(n) for n = 1..1206 (first 500 term from T. D. Noe)
H. Mishima, Factorization of Cyclotomic Numbers
Eric Weisstein's World of Mathematics, Cyclotomic Polynomial
Eric Weisstein's World of Mathematics, Mobius Transform
EXAMPLE
a(11) = 2 because cyclotomic(11,2) = 2047, which has two factors: 23 and 89.
MATHEMATICA
Join[{0}, Table[Plus@@Transpose[FactorInteger[Cyclotomic[n, 2]]][[2]], {n, 2, 100}]]
PROG
(PARI) a(n) = #factor(polcyclo(n, 2))~; \\ Michel Marcus, Mar 06 2015
CROSSREFS
KEYWORD
nonn
AUTHOR
T. D. Noe, Jun 19 2003
STATUS
approved