OFFSET
1,2
COMMENTS
No Bell number is divisible by 8. - John W. Layman, Jan 02 2002
LINKS
Vaclav Kotesovec, Table of n, a(n) for n = 1..134
J. W. Layman, Maximum zero strings of Bell numbers modulo primes, J. Comb. Th. A40 (1985),161-168.
G. T. Williams, Numbers generated by the function e^(e^x-1), Am. Math. Monthly 52 (1945),323-327.
MATHEMATICA
b[ n_ ] := Nest[ Factor[ D[ #1, x ] ] &, Exp[ Exp[ x - 1 ] - 1 ], n ] /. (x -> 1); Do[ k = 1; While[ c = b[ k ]; !IntegerQ[ c/n ], k++ ]; Print[ c ], {n, 1, 7} ]
CROSSREFS
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Dec 17 2001
EXTENSIONS
More terms from John W. Layman, Jan 02 2002
More terms from David Wasserman, Mar 31 2008
STATUS
approved