OFFSET
0,4
COMMENTS
From Robert Israel, Oct 23 2015: (Start)
If n = 2^k, a(n) = a(n-1).
If n = p^k where p is an odd prime and k >= 1, 2*n*a(n) = p*(n+1)*a(n-1).
If n is even and not a prime power, 2*a(n) = a(n-1).
If n is odd and not a prime power, 2*n*a(n) = (n+1)*a(n-1). (End)
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000
FORMULA
MAPLE
a := n -> lcm(seq(k, k=1..n))/binomial(n, iquo(n, 2)):
seq(a(n), n=0..49); # Peter Luschny, Oct 23 2015
MATHEMATICA
Join[{1}, Table[LCM @@ Range[n]/Binomial[n, Floor[n/2]], {n, 1, 50}]] (* or *) Table[Product[Cyclotomic[k, 1], {k, 2, n}]/Binomial[n, Floor[n/2]], {n, 0, 50}] (* G. C. Greubel, Apr 17 2017 *)
PROG
(PARI) A263673(n) = lcm(vector(n, i, i)) / binomial(n, n\2);
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Max Alekseyev, Oct 23 2015
STATUS
approved