OFFSET
1,2
COMMENTS
a(n) is the construction number of the complete graph K_n.
REFERENCES
P. C. Kainen, R. Strong, and J. Tilley, Problem 12401, Amer. Math. Monthly, 130 (2023), 587.
LINKS
Tauraso, R. Solution to Problem 12401.
Eric Weisstein's World of Mathematics, Complete Graph.
Eric Weisstein's World of Mathematics, Construction Number.
MATHEMATICA
Table[Binomial[n + 1, 2]!/(2 n - 1)!!, {n, 10}]
PROG
(Python)
from sympy import factorial, factorial2
def A374928(n): return int(factorial(n*(n+1)>>1)//factorial2((n<<1)-1)) # Chai Wah Wu, Jul 24 2024
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Eric W. Weisstein, Jul 24 2024
STATUS
approved