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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A158856 A triangle of polynomial coefficients: p(x,n)=If[n == 0, 1, (Sum[x^i, {i, 0, Floor[(n - 1)/2] + 1}])(Sum[(-x)^i, {i, 0, Floor[n/2]}])]. 0
1, 1, 1, 1, 0, -1, 1, 0, 0, -1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, -1, 0, -1, 1, 0, 1, 0, 0, -1, 0, -1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, -1, 0, -1, 0, -1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Row sums are:

{1, 2, 0, 0, 3, 4, 0, 0, 5, 6, 0...}.

LINKS

Table of n, a(n) for n=0..65.

FORMULA

p(x,n)=If[n == 0, 1, (Sum[x^i, {i, 0, Floor[(n - 1)/2] + 1}])(Sum[(-x)^i, {i, 0, Floor[n/2]}])];

t(n,m)=coefficients(p(x,n),x)

EXAMPLE

{1},

{1, 1},

{1, 0, -1},

{1, 0, 0, -1},

{1, 0, 1, 0, 1},

{1, 0, 1, 1, 0, 1},

{1, 0, 1, 0, -1, 0, -1},

{1, 0, 1, 0, 0, -1, 0, -1},

{1, 0, 1, 0, 1, 0, 1, 0, 1},

{1, 0, 1, 0, 1, 1, 0, 1, 0, 1},

{1, 0, 1, 0, 1, 0, -1, 0, -1, 0, -1}

MATHEMATICA

Clear[p, x, n, m, a];

p[x_, n_] = If[n == 0, 1, (Sum[x^i, {i, 0, Floor[(n - 1)/2] + 1}])(Sum[(-x)^i, {i, 0, Floor[n/2]}])];

Table[ExpandAll[p[x, n]], {n, 0, 10}];

Table[CoefficientList[ExpandAll[p[x, n]], x], {n, 0, 10}];

Flatten[%]

CROSSREFS

A154957

Sequence in context: A103452 A131219 A127970 * A154957 A140865 A114000

Adjacent sequences:  A158853 A158854 A158855 * A158857 A158858 A158859

KEYWORD

sign,tabl,uned

AUTHOR

Roger L. Bagula, Mar 28 2009

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
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 22 13:47 EST 2019. Contains 329393 sequences. (Running on oeis4.)