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A069135
a(n) = (n!*(n+1)!)^2.
1
1, 4, 144, 20736, 8294400, 7464960000, 13168189440000, 41295442083840000, 214075571762626560000, 1734012131277275136000000, 20981546788455029145600000000, 365582471242040427832934400000000, 8896815020146295851742291558400000000, 294698100727325903793111665580441600000000
OFFSET
0,2
FORMULA
a(n) = det(PS(i+2,j), 1 <= i,j <= n), where PS(n,k) are Legendre-Stirling numbers of the second kind (A071951) [Mircea Merca, Apr 04 2013]
a(n) = A010790(n)^2. - Michel Marcus, Jan 15 2023
MATHEMATICA
Table[(n!(n + 1)!)^2, {n, 1, 10}]
PROG
(PARI) a(n) = (n!*(n+1)!)^2; \\ Michel Marcus, Jan 15 2023
CROSSREFS
Sequence in context: A084703 A186418 A122747 * A186081 A375416 A138176
KEYWORD
nonn
AUTHOR
Rebecca Gladu (rgladu(AT)eve.assumption.edu), Apr 07 2002
EXTENSIONS
Edited and extended by Robert G. Wilson v, Apr 08 2002
More terms from Michel Marcus, Jan 15 2023
STATUS
approved