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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A100162 Structured disdyakis dodecahedral numbers (vertex structure 7). 4
1, 26, 117, 316, 665, 1206, 1981, 3032, 4401, 6130, 8261, 10836, 13897, 17486, 21645, 26416, 31841, 37962, 44821, 52460, 60921, 70246, 80477, 91656, 103825, 117026, 131301, 146692, 163241, 180990, 199981, 220256 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Also structured deltoidal icositetrahedral numbers (vertex structure 7) (cf. A100161 = alternate vertex).

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..5000

FORMULA

a(n) = (1/6)*(42*n^3 - 54*n^2 + 18*n).

G.f.: x*(1 + 22*x + 19*x^2)/(1-x)^4. - Colin Barker, Jan 19 2012

PROG

(MAGMA) [(1/6)*(42*n^3-54*n^2+18*n): n in [1..40]]; // Vincenzo Librandi, Jul 24 2011

CROSSREFS

Cf. A100161, A100163 = alternate vertices; A100145 for more on structured polyhedral numbers.

Cf. A260260 (comment). - Bruno Berselli, Jul 22 2015

Sequence in context: A251262 A221570 A100161 * A051729 A100163 A296325

Adjacent sequences:  A100159 A100160 A100161 * A100163 A100164 A100165

KEYWORD

nonn,easy

AUTHOR

James A. Record (james.record(AT)gmail.com), Nov 07 2004

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 September 16 10:36 EDT 2019. Contains 327094 sequences. (Running on oeis4.)