A378118 a(n) is the multinomial coefficient given by the previous terms, i.e., a(n) = (a(1)+...+a(n-1))!/(a(1)!*...*a(n-1)!).

1, 1, 2, 12, 21840, 2814355154336774377799951925175856161820370339122436787831200

Offset

1,3

Comments

a(7) = 6153915608...9019200000 (1235886 digits).

Links

Table of n, a(n) for n=1..6.

Example

a(1) = 1 (0! divided by the empty product).
a(2) = 1!/1! = 1.
a(3) = (1+1)!/(1!*1!) = 2.
a(4) = (1+1+2)!/(1!*1!*2!) = 12.
a(5) = (1+1+2+12)!/(1!*1!*2!*12!) = 21840.

Crossrefs

Sequence in context: A262032 A074200 A342104 * A274223 A280734 A048830

Adjacent sequences: A378114 A378115 A378117 * A378120 A378121 A378122

Keyword

nonn,new

Author

Pontus von Brömssen, Nov 17 2024

Status

approved