login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A123774 Number of ways to build a contiguous building with n LEGO blocks of size 1x3 on top of a fixed block of the same size. 0
14, 244, 5762, 147801, 4117161, 119893930, 3616711327, 111950012510, 3536272532516 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
The base block is not counted among the n and must be the only block in the bottom layer of the building
LINKS
CROSSREFS
Sequence in context: A286882 A326651 A055477 * A074815 A280122 A051622
KEYWORD
nonn,hard
AUTHOR
Søren Eilers, Oct 29 2006
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 29 02:23 EDT 2024. Contains 371264 sequences. (Running on oeis4.)