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

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A001789 Binomial(n,3)*2^(n-3).
(Formerly M4522 N1916)
22
1, 8, 40, 160, 560, 1792, 5376, 15360, 42240, 112640, 292864, 745472, 1863680, 4587520, 11141120, 26738688, 63504384, 149422080, 348651520, 807403520, 1857028096, 4244635648, 9646899200, 21810380800, 49073356800, 109924319232 (list; graph; refs; listen; history; internal format)
OFFSET

3,2

COMMENTS

Number of 3-dimensional cubes in n-dimensional hypercube - Henry Bottomley (se16(AT)btinternet.com), Apr 14 2000

With three leading zeros, this is the second binomial transform of (0,0,0,1,0,0,0,0,..) - Paul Barry (pbarry(AT)wit.ie), Mar 07 2003

With 3 leading zeros, binomial transform of C(n,3). - Paul Barry (pbarry(AT)wit.ie), Apr 10 2003

Let M=[1,0,i;0,1,0;i,0,1], i=sqrt(-1). Then 1/det(I-xM)=1/(1-2x)^4. - Paul Barry (pbarry(AT)wit.ie), Apr 27 2005

If X_1,X_2,...,X_n is a partition of a 2n-set X into 2-blocks then, for n>2, a(n+1) is equal to the number of (n+3)-subsets of X intersecting each X_i (i=1,2,...,n). - Milan R. Janjic (agnus(AT)blic.net), Jul 21 2007

With a different offset, number of n-permutations (n=4) of 3 objects: u, v, w with repetition allowed, containing exactly three u's. Example: a(1)=8 because we have: uuuv, uuvu, uvuu, vuuu, uuuw, uuwu, uwuu and wuuu - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jun 03 2008

With offset 0, a(n) is the number of ways to seperate [n] into four non-overlapping intervals (allowed to be empty) and then choose a subset from each interval. [From Geoffrey Critzer (critzer.geoffrey(AT)usd443), Feb 07 2009]

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. 796.

H. J. Brothers, Pascal's Prism: Supplementary Material, http://www.brotherstechnology.com/docs/Pascal's_Prism_(supplement).pdf.

H. Izbicki, Ueber Unterbaeume eines Baumes, Monatshefte f\"{u}r Mathematik, 74 (1970), 56-62.

Jones, C. W.; Miller, J. C. P.; Conn, J. F. C.; Pankhurst, R. C.; Tables of Chebyshev polynomials. Proc. Roy. Soc. Edinburgh. Sect. A. 62, (1946). 187-203.

Dusko Letic, Nenad Cakic, Branko Davidovic, Ivana Berkovic and Eleonora Desnica, Some certain properties of the generalized hypercubical functions, Advances in Difference Equations,

2011, 2011:60; http://www.advancesindifferenceequations.com/content/pdf/1687-1847-2011-60.pdf.

Clifford A. Pickover, The Math Book, From Pythagoras to the 57th Dimension, 250 Milestones in the History of Mathematics, Sterling Publ., NY, 2009, page 282.

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=3..500

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].

Milan Janjic, Two Enumerative Functions

S. Plouffe, Approximations de S\'{e}ries G\'{e}n\'{e}ratrices et Quelques Conjectures, Dissertation, Universit\'{e} du Qu\'{e}bec \`{a} Montr\'{e}al, 1992.

S. Plouffe, 1031 Generating Functions and Conjectures, Universit\'{e} du Qu\'{e}bec \`{a} Montr\'{e}al, 1992.

Eric Weisstein's World of Mathematics, Hypercube

Index entries for sequences related to Chebyshev polynomials.

FORMULA

a(n)=2*a(n-1)+A001788(n-1)

G.f. (with three leading zeros): x^3/(1-2x)^4. With three leading zeros, a(n)=8a(n-1)-24a(n-2)+32a(n-3)-16a(n-4), a(0)=a(1)=a(2)=0, a(3)=1. - Paul Barry (pbarry(AT)wit.ie), Mar 07 2003

E.g.f. (x^3/3!)exp(2x) (with 3 leading zeros) - Paul Barry (pbarry(AT)wit.ie), Apr 10 2003

MAPLE

seq((n^3-n)*2^(n-3)/3, n=2..27); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Apr 25 2007

A001789:=1/(2*z-1)**4; [Conjectured by S. Plouffe in his 1992 dissertation.]

seq(binomial(n+3, 3)*2^n, n=0..25); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jun 03 2008

MATHEMATICA

Table[Binomial[n, 3]*2^(n - 3), {n, 3, 100}] - Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Apr 18 2006

PROG

(Other) SAGE: [lucas_number1(n, 2, 0)*binomial(n, 3)/4 for n in xrange(3, 29)] [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Mar 10 2009]

CROSSREFS

Cf. A001787, A001788, A003472.

For n>0, a(n+3) = 2 * A082138(n) = 8 * A080930(n+1).

Sequence in context: A125198 A128639 A004405 * A074412 A113071 A006726

Adjacent sequences:  A001786 A001787 A001788 * A001790 A001791 A001792

KEYWORD

nonn,easy,nice,changed

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

EXTENSIONS

More terms from James A. Sellers (sellersj(AT)math.psu.edu), Apr 15 2000

More terms from Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Apr 18 2006

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

Content is available under The OEIS End-User License Agreement .

Last modified February 17 02:48 EST 2012. Contains 205978 sequences.