The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
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!)
A061525 Surround numbers of an n X 2 rectangle when n is odd. 1
83, 361, 951, 1997, 3667, 6153, 9671, 14461, 20787, 28937, 39223, 51981, 67571, 86377, 108807, 135293, 166291, 202281, 243767, 291277, 345363, 406601, 475591, 552957, 639347, 735433, 841911, 959501, 1088947, 1231017, 1386503, 1556221 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
See A061524 for even n.
LINKS
E. J. Friedman, Math. Magic: May, 1999
FORMULA
a(n) = (n^4 + 32n^3 + 278n^2 + 656n + 361)/16 when n is odd.
From Chai Wah Wu, Dec 20 2019: (Start)
a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n > 5.
G.f.: x*(3*x^4 - 22*x^3 + 24*x^2 + 54*x - 83)/(x - 1)^5. (End)
CROSSREFS
Sequence in context: A031433 A177099 A327850 * A293979 A340861 A160359
KEYWORD
easy,nonn
AUTHOR
Jason Earls, May 03 2001
EXTENSIONS
More terms from Larry Reeves (larryr(AT)acm.org), May 07 2001
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 May 18 14:46 EDT 2024. Contains 372636 sequences. (Running on oeis4.)