A100172 Structured triakis icosahedral numbers (vertex structure 4).

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

Links

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

Index entries for linear recurrences with constant coefficients, signature (4,-6,4,-1).

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

Adjacent sequences: A100169 A100170 A100171 * A100173 A100174 A100175

Keyword

easy,nonn

Author

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

Status

approved