OFFSET
1,2
COMMENTS
a(n) is the numerator of (n/(n-1)) * ((n-3)/(n-2)) * ((n-4)/(n-5)) ...
FORMULA
a(n) = numerator of (n*A337355(n-2))/(a(n-2)*(n-1)) for n>=3.
EXAMPLE
a(n)/A337355(n) equals 1, 2, 3/2, 2/3, 5/6, 9/5, 7/5, 40/63, 45/56, 7/4 ...
a(4) = numerator of (4*1)/(3*2) = numerator of 2/3 = 2.
a(5) = numerator of (5*2)/(4*3) = numerator of 5/6 = 5.
12 * 9*8 * 5*4 * 1
a(12) = numerator of --------------------------- = 48.
11*10 * 7*6 * 3*2
PROG
(PARI) a(n) = {numerator(prod(i=0, n-1, (n-i)^(-1)^((i+1)\2)))} \\ Andrew Howroyd, Aug 24 2020
CROSSREFS
KEYWORD
nonn,frac
AUTHOR
Devansh Singh, Aug 24 2020
EXTENSIONS
Terms a(31) and beyond from Andrew Howroyd, Aug 25 2020
STATUS
approved