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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A171589 Riordan array (f(x), x*f(x)) where f(x) is the g.f. of A104455. 2
1, 4, 1, 17, 8, 1, 77, 50, 12, 1, 371, 290, 99, 16, 1, 1890, 1647, 703, 164, 20, 1, 10095, 9366, 4644, 1380, 245, 24, 1, 56040, 53853, 29592, 10434, 2385, 342, 28, 1, 320795, 314234, 185411, 74084, 20345, 3782, 455, 32, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Equal to B*A171568 = A125906*B^(-1), B = A007318.

LINKS

Table of n, a(n) for n=0..44.

FORMULA

T(n,0)-T(n,1)=3^n.

T(n,k) = T(n-1,k-1) + 4*T(n-1,k) + sum_{i, i>=0} T(n-1,k+1+i). - Philippe Deléham, Feb 23 2012

EXAMPLE

Triangle begins :

1

4, 1

17, 8, 1

77, 50, 12, 1

371, 290, 99, 16, 1

1890, 1647, 703, 164, 20, 1

10095, 9366, 4644, 1380, 245, 24, 1

Production matrix begins

4, 1

1, 4, 1

1, 1, 4, 1

1, 1, 1, 4, 1

1, 1, 1, 1, 4, 1

1, 1, 1, 1, 1, 4, 1

1, 1, 1, 1, 1, 1, 4, 1

1, 1, 1, 1, 1, 1, 1, 4, 1

... - Philippe Deléham, Mar 05 2013

CROSSREFS

Cf. A104455, A125906, A171568,

Sequence in context: A301624 A126791 A052179 * A126331 A013631 A113355

Adjacent sequences:  A171586 A171587 A171588 * A171590 A171591 A171592

KEYWORD

nonn,tabl

AUTHOR

Philippe Deléham, Dec 12 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 July 17 18:47 EDT 2019. Contains 325109 sequences. (Running on oeis4.)