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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A100185 Structured meta-anti-prism numbers, the n-th number from a structured n-gonal anti-prism number sequence. 9
1, 4, 19, 68, 185, 416, 819, 1464, 2433, 3820, 5731, 8284, 11609, 15848, 21155, 27696, 35649, 45204, 56563, 69940, 85561, 103664, 124499, 148328, 175425, 206076, 240579, 279244, 322393, 370360, 423491, 482144 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..10000

Index entries for linear recurrences with constant coefficients, signature (5,-10,10,-5,1).

FORMULA

a(n)=(1/6)*(3*n^4-8*n^3+9*n^2+2*n).

G.f.: x*(1-x+9*x^2+3*x^3)/(1-x)^5. [Colin Barker, Jun 08 2012]

EXAMPLE

There are no 1- or 2-gonal anti-prisms, so 1 and (2n) are used as the first and second terms since all the sequences begin as such.

PROG

(MAGMA) [(1/6)*(3*n^4-8*n^3+9*n^2+2*n): n in [1..40]]; // Vincenzo Librandi, Aug 03 2011

CROSSREFS

Cf. A005900, A000447, A096000, A100178, A100157, A100185 - structured anti-prisms; A006484 for other structured meta numbers; and A100145 for more on structured numbers.

Sequence in context: A212039 A055485 A000306 * A291888 A217324 A129019

Adjacent sequences:  A100182 A100183 A100184 * A100186 A100187 A100188

KEYWORD

easy,nonn

AUTHOR

James A. Record (james.record(AT)gmail.com)

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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 22 09:57 EDT 2018. Contains 316433 sequences. (Running on oeis4.)