|
|
A129893
|
|
a(n) = s!/(s-n)! where s = (n*(n+1)/2)+1.
|
|
2
|
|
|
1, 2, 12, 210, 7920, 524160, 53721360, 7866331200, 1556675366400, 399790821830400, 129210868410624000, 51295616536721356800, 24529502681864788608000, 13903600298770901182464000
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,2
|
|
COMMENTS
|
Bread Shop Open!. We have a loaf of bread which has a kernel of corns irregularly inside. We cut the loaf n times getting the maximal number (s, see A000124) of pieces and distribute one piece to each of n people. The remaining pieces of bread will be the prize for the winner. The sequence gives the number of cases when n pieces are distributed to n persons.
|
|
REFERENCES
|
L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 72, Problem 2.
H. E. Dudeney, Amusements in Mathematics, Nelson, London, 1917, page 177.
N. Reading, On the structure of Bruhat Order, Ph.D. dissertation, University of Minnesota, anticipated 2002.
A. M. Robert, A Course in p-adic Analysis, Springer-Verlag, 2000; p. 213.
N. J. A. Sloane, On single-deletion-correcting codes, in Codes and Designs (Columbus, OH, 2000), 273-291, Ohio State Univ. Math. Res. Inst. Publ., 10, de Gruyter, Berlin, 2002.
W. A. Whitworth, DCC Exercises in Choice and Chance, Stechert, NY, 1945, p. 30.
A. M. Yaglom and I. M. Yaglom: Challenging Mathematical Problems with Elementary Solutions. Vol. I. Combinatorial Analysis and Probability Theory. New York: Dover Publications, Inc., 1987, p. 13, #44 (First published: San Francisco: Holden-Day, Inc., 1964)
|
|
LINKS
|
|
|
FORMULA
|
a(n) = sPn, where s=(n*(n+1)/2)+1.
|
|
EXAMPLE
|
a(2)=12 s=4,n=2 because we can write 12=4*3.
a(3)=210 s=7,n=3 because we can write 210=7*6*5.
|
|
MATHEMATICA
|
Table[s=(n(n+1))/2+1; s!/(s-n)!, {n, 0, 20}] (* Harvey P. Dale, Nov 15 2012 *)
#[[1]]!/(#[[1]]-#[[2]])!&/@With[{nn=20}, Thread[{Accumulate[ Range[0, nn]]+ 1, Range[0, nn]}]] (* Harvey P. Dale, Sep 12 2015 *)
|
|
PROG
|
(Haskell)
a129893 n = a129893_list !! n
a129893_list = 1 : zipWith div (tail fs) fs where
fs = map a000142 a000124_list
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,nice
|
|
AUTHOR
|
Kim Dong Seok (Go Jae Song, Nam Dae Young) from KNU (gjs0419(AT)nate.com), Jun 04 2007
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|