|
| |
|
|
A092988
|
|
Least number k < n such that n*k has the maximum number of divisors.
|
|
1
| |
|
|
1, 2, 3, 4, 4, 6, 6, 8, 6, 6, 10, 12, 12, 12, 15, 12, 10, 12, 18, 20, 18, 12, 15, 24, 24, 20, 15, 24, 28, 24, 30, 20, 30, 24, 35, 36, 30, 20, 36, 36, 40, 36, 30, 28, 30, 36, 35, 48, 36, 40, 45, 48, 40, 48, 45, 40, 30, 48, 42, 60, 60, 40, 45, 48, 60, 60, 60, 60, 36, 60, 70, 60, 60
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 2,2
|
|
|
EXAMPLE
| a(14) = 6 as 14*6 = 84= 2^2*3*7 has 12 divisors, though 14*9 = 126 = 3^2*2*7 also has 12 divisors but 9 > 6.
a(15) = 12 as 180 has 18 divisors 15*14 = 210 has 16 divisors.
|
|
|
MATHEMATICA
| Do[x = y = 0; For[k = 1, k < n, k++, d = Length[Divisors[n*k]]; If[d > x, x = d; y = k]]; Print[y], {n, 2, 50}] (Propper)
|
|
|
CROSSREFS
| Cf. A092989.
Sequence in context: A160680 A061984 A063208 * A138768 A111939 A003962
Adjacent sequences: A092985 A092986 A092987 * A092989 A092990 A092991
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Mar 28 2004
|
|
|
EXTENSIONS
| 35 more terms from Ryan Propper (rpropper(AT)stanford.edu), Jul 25 2005
More terms from David Wasserman (dwasserm(AT)earthlink.net), Aug 22 2006
|
| |
|
|
