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!)
A127276 Hankel transform of A127275. 7
1, 1, -2, -16, -64, -208, -608, -1664, -4352, -11008, -27136, -65536, -155648, -364544, -843776, -1933312, -4390912, -9895936, -22151168, -49283072, -109051904, -240123904, -526385152, -1149239296, -2499805184, -5419040768 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

The inverse binomial transform of this sequence yields 1, 0, -3, -8,..., which is 1 followed by the negated terms of A005563. [Paul Curtz, Dec 07 2010]

The smallest odd prime divisor of a(n) is >= 13. - Vladimir Shevelev, Feb 03 2014

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

FORMULA

Conjecture: G.f.: -(4*x-1)*(x-1) / ( (2*x-1)^3 ) and a(n) = 2^n-n*(n+1)*2^(n-2). - R. J. Mathar, Dec 11 2010

a(n) = A178987(n) - A178987(n+1). - Klaus Brockhaus, Jan 08 2011

MAPLE

A127276:=n->2^n - n*(n + 1)*2^(n - 2); seq(A127276(n), n=0..26); # Wesley Ivan Hurt, Dec 02 2013

MATHEMATICA

Table[2^n - n*(n + 1)*2^(n - 2), {n, 0, 26}] (* Wesley Ivan Hurt, Dec 02 2013 *)

PROG

(MAGMA) [2^n-n*(n+1)*2^(n-2): n in [0..30]]; // Vincenzo Librandi, Aug 11 2011

CROSSREFS

Cf. A076616, A176126, A236999.

Sequence in context: A183762 A061608 A212899 * A076616 A222381 A110048

Adjacent sequences:  A127273 A127274 A127275 * A127277 A127278 A127279

KEYWORD

sign

AUTHOR

Paul Barry, Jan 10 2007

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 11 20:03 EDT 2020. Contains 335652 sequences. (Running on oeis4.)