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A100170
Structured pentagonal hexacontahedral numbers (vertex structure 10).
2
1, 92, 444, 1228, 2615, 4776, 7882, 12104, 17613, 24580, 33176, 43572, 55939, 70448, 87270, 106576, 128537, 153324, 181108, 212060, 246351, 284152, 325634, 370968, 420325, 473876, 531792, 594244, 661403, 733440, 810526, 892832
OFFSET
1,2
FORMULA
a(n) = (1/6)*(171*n^3 - 243*n^2 + 78*n).
G.f.: x*(1 + 88*x + 82*x^2)/(1-x)^4. - Colin Barker, Feb 14 2012
PROG
(Magma) [(1/6)*(171*n^3-243*n^2+78*n): n in [1..40]]; // Vincenzo Librandi, Jul 27 2011
(PARI) a(n)=n*(171*n^2-243*n+78)/6 \\ Charles R Greathouse IV, Feb 06 2012
CROSSREFS
Cf. A100169 = alternate vertex; A100145 for more on structured numbers.
Sequence in context: A246802 A302351 A100169 * A233311 A233309 A205992
KEYWORD
easy,nonn
AUTHOR
James A. Record (james.record(AT)gmail.com), Nov 07 2004
STATUS
approved