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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A137696 Triangular sequence of coefficients from a polynomial recursion: p(x,n)=p(x,Floor[(n-1)/2])-x^2*p(x,n-3)+x. 0
1, 0, 1, 0, 1, 1, 0, 2, -1, 0, 2, 0, -1, 0, 2, 1, -1, -1, 0, 2, 1, -2, 1, 0, 3, -1, -2, 0, 1, 0, 3, -1, -2, -1, 1, 1, 0, 3, 0, -3, -1, 2, -1, 0, 3, 0, -4, 1, 2, 0, -1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,8

COMMENTS

Row sums are: {1, 1, 2, 1, 1, 1, 2, 1, 1, 0, 1, ...}

LINKS

Table of n, a(n) for n=1..51.

FORMULA

p(x,n)=p(x,Floor[(n-1)/2])-x^2*p(x,n-3)+x; out_n,m=Coefficient(p(x,n)).

EXAMPLE

{1},

{0, 1},

{0, 1, 1},

{0, 2, -1},

{0, 2, 0, -1},

{0, 2, 1, -1, -1},

{0, 2, 1, -2, 1},

{0, 3, -1, -2, 0, 1},

{0, 3, -1, -2, -1,1, 1},

{0, 3, 0, -3, -1, 2, -1},

{0, 3, 0, -4, 1, 2, 0, -1}

MATHEMATICA

Clear[p, x]; p[x, -1] = 0; p[x, 0] = 1; p[x, 1] = x; p[x, 2] = x^2 + x; p[x_, n_] := p[x, n] = p[x, Floor[(n - 1)/2]] - x^2*p[x, n - 3] + x; Table[ExpandAll[p[x, n]], {n, 0, 10}]; a = Table[CoefficientList[p[x, n], x], {n, 0, 10}]; Flatten[a] Table[Apply[Plus, CoefficientList[p[x, n], x]], {n, 0, 10}];

CROSSREFS

Sequence in context: A033792 A033768 A033786 * A275731 A143614 A071412

Adjacent sequences:  A137693 A137694 A137695 * A137697 A137698 A137699

KEYWORD

tabl,sign

AUTHOR

Roger L. Bagula, Apr 27 2008

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 February 23 09:40 EST 2018. Contains 299509 sequences. (Running on oeis4.)