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

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A142965 One fourth of third column (m=2) of triangle A142963. 6
1, 18, 129, 646, 2685, 10002, 34777, 115566, 372453, 1175290, 3654369, 11245110, 34349005, 104373282, 315969705, 954002878, 2874983541, 8652474378, 26015617585, 78169534470, 234766551261, 704840716978, 2115654610809, 6349329417486, 19052920751365, 57169029907482 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

FORMULA

a(n)= A142693(n+3,2)/4.

Contribution from Johannes W. Meijer (meijgia(AT)hotmail.com), Feb 20 2009: (Start)

a(n) = 10a(n-1)-40a(n-2)+82a(n-3)-91a(n-4)+52a(n-5)-12a(n-6)

a(n) = 35/2+2*n^2+12*n-84*2^n-24*2^n*n+135/2*3^n

G.f.: (1+8*z-11*z^2-6*z^3)/((1-z)^3*(1-2*z)^2*(1-3*z))

(End)

MATHEMATICA

LinearRecurrence[{10, -40, 82, -91, 52, -12}, {1, 18, 129, 646, 2685, 10002}, 30] (* or *) CoefficientList[Series[(1+8x-11x^2-6x^3)/((x-1)^3 (2x-1)^2 (3x-1)), {x, 0, 30}], x] (* From Harvey P. Dale, Apr 24 2011 *)

CROSSREFS

Column m=1: 2*A142964; m=3: 8*A142966.

Contribution from Johannes W. Meijer (meijgia(AT)hotmail.com), Feb 20 2009: (Start)

Cf. A156925

Equals A156920(n+2,2)

Equals A156919(n+2,2)/2^n

(End)

Sequence in context: A056125 A027566 A041620 * A058649 A103308 A010824

Adjacent sequences:  A142962 A142963 A142964 * A142966 A142967 A142968

KEYWORD

nonn,easy

AUTHOR

Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de) Sep 15 2008

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 15 16:56 EST 2012. Contains 205825 sequences.