

A100185


Structured metaantiprism numbers, the nth number from a structured ngonal antiprism 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
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OFFSET

1,2


LINKS



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)/(1x)^5. [Colin Barker, Jun 08 2012]


EXAMPLE

There are no 1 or 2gonal antiprisms, 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^48*n^3+9*n^2+2*n): n in [1..40]]; // Vincenzo Librandi, Aug 03 2011


CROSSREFS



KEYWORD

easy,nonn


AUTHOR

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


STATUS

approved



