OFFSET
0,3
LINKS
Andrew Howroyd, Table of n, a(n) for n = 0..30
FORMULA
PROG
(PARI) a(n)={binomial(n, 2)!*sum(k=0, binomial(n, 2), 1/k!)} \\ Andrew Howroyd, Feb 12 2020
CROSSREFS
KEYWORD
nonn
AUTHOR
Christian G. Bower, Jan 13 2004
EXTENSIONS
a(0)=1 prepended and terms a(10) and beyond from Andrew Howroyd, Feb 12 2020
STATUS
approved