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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)!).
0
1, 1, 2, 12, 21840, 2814355154336774377799951925175856161820370339122436787831200
OFFSET
1,3
COMMENTS
a(7) = 6153915608...9019200000 (1235886 digits).
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
KEYWORD
nonn
AUTHOR
STATUS
approved