OFFSET
1,1
EXAMPLE
a(4) = A178901(4)/4 = 12/4 = 3.
PROG
(PARI) lista(nn) = {my(va = vector(nn)); va[1] = 2; for (n=2, nn, va[n] = (2*(n-1)*va[n-1]\n); ); va; } \\ Michel Marcus, Dec 18 2020
CROSSREFS
KEYWORD
nonn
AUTHOR
J. Lowell, Dec 16 2020
STATUS
approved