|
|
A008339
|
|
a(1)=1; for n >= 1, a(n+1) = lcm(a(n),n) / gcd(a(n),n).
|
|
5
|
|
|
1, 1, 2, 6, 6, 30, 5, 35, 280, 2520, 252, 2772, 231, 3003, 858, 1430, 5720, 97240, 437580, 8314020, 415701, 969969, 176358, 4056234, 2704156, 67603900, 2600150, 70204050, 10029150, 290845350, 9694845, 300540195, 9617286240, 35263382880, 1037158320
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,3
|
|
COMMENTS
|
a(n+1) is divisible by all primes in (n/2, n]; thus lim_{n->infinity} a(n) = infinity. - Franklin T. Adams-Watters, Dec 13 2006
|
|
LINKS
|
|
|
FORMULA
|
a(1) = 1, a(n) = a(n-1)*r/s where y is the largest divisor of a(n-1) with r*s = n. - Amarnath Murthy, Jul 01 2003
|
|
MAPLE
|
A008339 := proc(n) option remember; if n = 1 then 1 else lcm(A008339(n-1), n-1)/gcd(A008339(n-1), n-1); fi; end;
|
|
MATHEMATICA
|
FoldList[ LCM[ #1, #2 ]/GCD[ #1, #2 ]&, 1, Range[ 30 ] ] (* Olivier Gérard, Aug 15 1997 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|