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A074199
a(n) = n!/(1!*2!*3!*...*k!) where k is the largest integer such that 1!*2!*3!*...*k! divides n!.
4
1, 1, 3, 2, 10, 60, 420, 140, 1260, 105, 1155, 13860, 180180, 2522520, 37837800, 840840, 14294280, 51051, 969969, 19399380, 407386980, 8962513560, 206137811880, 4947307485120, 123682687128000, 79755701025, 2153403927675, 60295309974900, 1748563989272100, 52456919678163000
OFFSET
1,3
LINKS
FORMULA
a(n) = n!/A000178(A074198(n)). - Amiram Eldar, May 14 2024
MATHEMATICA
a[n_] := Module[{k = 1}, NestWhile[# / (++k)! &, n!, IntegerQ] * k!]; Array[a, 30] (* Amiram Eldar, May 14 2024 *)
PROG
(PARI) a(n)=n!/prod(i=1, if(n<0, 0, s=1; while(n!%prod(i=1, s, i!)==0, s++); s-1), i!)
CROSSREFS
Similar to but different from A088302.
Sequence in context: A335719 A096073 A088302 * A153187 A248242 A215598
KEYWORD
easy,nonn
AUTHOR
Benoit Cloitre, Sep 17 2002
EXTENSIONS
More terms from Amiram Eldar, May 14 2024
STATUS
approved