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A100172
Structured triakis icosahedral numbers (vertex structure 4).
2
1, 32, 150, 412, 875, 1596, 2632, 4040, 5877, 8200, 11066, 14532, 18655, 23492, 29100, 35536, 42857, 51120, 60382, 70700, 82131, 94732, 108560, 123672, 140125, 157976, 177282, 198100, 220487, 244500, 270196, 297632
OFFSET
1,2
FORMULA
a(n) = (1/6)*(57*n^3 - 81*n^2 + 30*n).
G.f.: x*(1 + 28*x + 28*x^2)/(1-x)^4. [Colin Barker, May 29 2012]
MATHEMATICA
LinearRecurrence[{4, -6, 4, -1}, {1, 32, 150, 412}, 50] (* Harvey P. Dale, Sep 18 2023 *)
PROG
(Magma) [(1/6)*(57*n^3-81*n^2+30*n): n in [1..40]]; // Vincenzo Librandi, Jul 27 2011
CROSSREFS
Cf. A100164 = alternate vertex; A100145 for more on structured numbers.
Sequence in context: A100173 A234874 A220975 * A234132 A203557 A124998
KEYWORD
easy,nonn
AUTHOR
James A. Record (james.record(AT)gmail.com), Nov 07 2004
STATUS
approved