login
This site is supported by donations to The OEIS Foundation.

 

Logo

"Email this user" was broken Aug 14 to 9am Aug 16. If you sent someone a message in this period, please send it again.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A000453 Stirling numbers of the second kind, S(n,4).
(Formerly M4722 N2018)
12
1, 10, 65, 350, 1701, 7770, 34105, 145750, 611501, 2532530, 10391745, 42355950, 171798901, 694337290, 2798806985, 11259666950, 45232115901, 181509070050, 727778623825, 2916342574750, 11681056634501, 46771289738810, 187226356946265, 749329038535350 (list; graph; refs; listen; history; text; internal format)
OFFSET

4,2

COMMENTS

Given a set {1,2,3,4}, a(n) is the number of occurrences where the first 2 comes after the first '1', the first '3' after the first '2' and the first '4' after the first '3' in a list of n+3. For example, a(1): 1234; a(2): 11234, 12134, 12314, 12341, 12234, 12324, 12342, 12334, 12343, 12344. Related to the cereal box problem. - Kevin Nowaczyk (beakerboy99(AT)yahoo.com), Aug 02 2007

REFERENCES

M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 835.

F. N. David, M. G. Kendall and D. E. Barton, Symmetric Function and Allied Tables, Cambridge, 1966, p. 223.

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

T. D. Noe, Table of n, a(n) for n = 4..200

M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards, Applied Math. Series 55, Tenth Printing, 1972 [alternative scanned copy].

J. Brandts and C. Cihangir, Counting triangles that share their vertices with the unit n-cube, in Conference Applications of Mathematics 2013 in honor of the 70th birthday of Karel Segeth. Jan Brandts, Sergey Korotov, et al., eds., Institute of Mathematics AS CR, Prague 2013;

M. Griffiths, I. Mezo, A generalization of Stirling Numbers of the Second Kind via a special multiset, JIS 13 (2010) #10.2.5

INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 347

Simon Plouffe, Approximations de séries génératrices et quelques conjectures, Dissertation, Université du Québec à Montréal, 1992.

Simon Plouffe, 1031 Generating Functions and Conjectures, Université du Québec à Montréal, 1992.

Index entries for linear recurrences with constant coefficients, signature (10, -35, 50, -24).

FORMULA

G.f.: x^4/((1-x)*(1-2*x)*(1-3*x)*(1-4*x)).

E.g.f. ((exp(x)-1)^4)/4!.

a(n) = (4^n-4*3^n+6*2^n-4)/24. - Kevin Nowaczyk (beakerboy99(AT)yahoo.com), Aug 02 2007

a(n) = det(|s(i+4,j+3)|, 1 <= i,j <= n-4), where s(n,k) are Stirling numbers of the first kind. - Mircea Merca, Apr 06 2013

MAPLE

A000453:=1/(z-1)/(3*z-1)/(2*z-1)/(4*z-1); # conjectured by Simon Plouffe in his 1992 dissertation

MATHEMATICA

t={}; Do[f=StirlingS2[n, 4]; AppendTo[t, f], {n, 120}]; t (* Vladimir Joseph Stephan Orlovsky, Sep 27 2008 *)

CoefficientList[Series[1/((1 - x) (1 - 2 x) (1 - 3 x) (1 - 4 x)), {x, 0, 25}], x] (* Vladimir Joseph Stephan Orlovsky, Jun 20 2011 *)

LinearRecurrence[{10, -35, 50, -24}, {1, 10, 65, 350}, 100] (* Vladimir Joseph Stephan Orlovsky, Feb 23 2012 *)

PROG

(PARI) a(n)=(4^n-4*3^n+6*2^n-4)/24 \\ Charles R Greathouse IV, Sep 24 2015

CROSSREFS

Cf. A008277 (Stirling2 triangle), A016269, A056280 (Mobius transform).

Sequence in context: A022638 A003519 A056280 * A097791 A212259 A198848

Adjacent sequences:  A000450 A000451 A000452 * A000454 A000455 A000456

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified August 19 19:25 EDT 2017. Contains 290821 sequences.