login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A103778 Inverse of trinomial triangle A071675. 1

%I

%S 1,0,1,0,-1,1,0,1,-2,1,0,0,3,-3,1,0,-4,-2,6,-4,1,0,14,-7,-7,10,-5,1,0,

%T -30,36,-6,-16,15,-6,1,0,33,-96,63,3,-30,21,-7,1,0,55,154,-209,88,25,

%U -50,28,-8,1,0,-429,0,429,-374,99,66,-77,36,-9,1,0,1365,-1014

%N Inverse of trinomial triangle A071675.

%C Inverse of Riordan array (1, x(1+x+x^2)) (A071675).

%F Riordan array (1, y) where y satisfies y + y^2 + y^3 = x; y = -2^(2/3)*((3*sqrt(3)*sqrt(27*x^2 + 14*x + 3) - 27*x - 7)^(1/3) - (3*sqrt(3)*sqrt(27*x^2 + 14*x + 3) + 27*x + 7)^(1/3) + 2^(1/3))/6.

%e Rows start

%e {1},

%e {0,1},

%e {0,-1,1},

%e {0,1,-2,1},

%e {0,0,3,-3,1},

%e ...

%Y Cf. A071675.

%K easy,sign,tabl

%O 0,9

%A _Paul Barry_, Feb 15 2005

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 October 17 00:35 EDT 2021. Contains 348048 sequences. (Running on oeis4.)