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A093886 Least k such that k! is divisible by (1!*2!*3!...n!). 1
1, 2, 4, 8, 10, 16, 18, 26, 32, 40, 48, 60, 68, 80, 92, 108, 124, 136, 154, 172, 192, 208, 228, 252, 272, 296, 320, 344, 368, 394, 420, 452, 484, 512, 544, 580, 616, 648, 686, 724, 764, 800, 840, 880, 922, 964, 1008, 1050, 1096, 1144, 1192, 1240, 1288, 1340 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

k < n(n+1)/2 as n! divides every product of n successive integers.

EXAMPLE

a(4) = 8 as 1!*2!*3!*4! = 288 divides 8!= 40320 but not 7! = 5040.

MAPLE

a:=proc(n) local A, k: A:={}: for k from 1 to n*(n+1)/2 do if type(k!/product(j!, j=1..n), integer)=true then A:=A union {k} else A:=A fi od: A[1]; end: seq(a(n), n=1..60); # not necessarily the best Maple program (Deutsch)

CROSSREFS

Cf. A093887.

Sequence in context: A125021 A085406 A022340 * A125732 A032533 A062884

Adjacent sequences:  A093883 A093884 A093885 * A093887 A093888 A093889

KEYWORD

nonn

AUTHOR

Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Apr 23 2004

EXTENSIONS

More terms from Emeric Deutsch (deutsch(AT)duke.poly.edu), Feb 03 2006

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Last modified February 17 07:41 EST 2012. Contains 205998 sequences.