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!)
A137155 a(n) = Sum_{k=0..[n/2]} C(2^k + n-2k-1, n-2k); equals the antidiagonal sums of triangle A137153. 2
1, 1, 2, 3, 5, 9, 17, 35, 80, 201, 561, 1771, 6298, 25217, 115440, 605243, 3609754, 24742305, 196470603, 1792166979, 18817616610, 230233601737, 3268914688382, 53509699527491, 1020486454701731, 22777217813040393, 589097686208575727 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..26.

PROG

(PARI) a(n)=sum(k=0, n\2, binomial(2^k+n-2*k-1, n-2*k))

CROSSREFS

Cf. A137153, A137154.

Sequence in context: A166286 A179807 A110113 * A014227 A334816 A064769

Adjacent sequences:  A137152 A137153 A137154 * A137156 A137157 A137158

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Jan 24 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
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified February 25 22:37 EST 2021. Contains 341618 sequences. (Running on oeis4.)