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A088302
Smallest integer value of n!/(2!3!...p!), where denominator contains product of factorials of primes in increasing order.
4
1, 3, 2, 10, 60, 420, 28, 252, 2520, 27720, 66, 858, 12012, 180180, 2882880, 49008960, 882161280, 16761064320, 8398, 176358, 3879876, 89237148, 2141691552, 53542288800, 1392099508800, 37586686737600, 1052427228652800
OFFSET
2,2
COMMENTS
n!/{prime(1)!*prime(2)!*prime(3)!...*prime(k)!} where k is the largest integer such that {prime(1)!*prime(2)!*prime(3)!...*prime(k)!} divides n!.
EXAMPLE
a(8) = 8!/2!3!5! = 28, as 28/7! is not an integer.
a(12) = 12!/{2!*3!*5!*7!} = 66.
MATHEMATICA
f[n_] := Block[{k = 1}, While[ IntegerQ[ n!/Product[ Prime[i]!, {i, k}]], k++ ]; n!/Product[Prime[i]!, {i, k - 1}]]; Table[ f[n], {n, 2, 28}] (* Robert G. Wilson v, Jun 21 2004 *)
CROSSREFS
Similar to but different from A074199.
Sequence in context: A107334 A335719 A096073 * A074199 A153187 A248242
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Sep 30 2003
EXTENSIONS
More terms from Ray Chandler, Oct 06 2003
Edited by N. J. A. Sloane at the suggestion of Andrew S. Plewe, Jun 08 2007
STATUS
approved