A100167 Structured pentagonal icositetrahedral numbers (vertex structure 13).

1, 38, 171, 460, 965, 1746, 2863, 4376, 6345, 8830, 11891, 15588, 19981, 25130, 31095, 37936, 45713, 54486, 64315, 75260, 87381, 100738, 115391, 131400, 148825, 167726, 188163, 210196, 233885, 259290, 286471, 315488

Offset

1,2

Links

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

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

Formula

a(n) = (1/6)*(60*n^3 - 72*n^2 + 18*n).

G.f.: x*(1 + 34*x + 25*x^2)/(1-x)^4. - Colin Barker, Feb 14 2012

Mathematica

Table[(60n^3-72n^2+18n)/6, {n, 40}] (* or *) LinearRecurrence[{4, -6, 4, -1}, {1, 38, 171, 460}, 40] (* Harvey P. Dale, Aug 21 2016 *)

Prog

(Magma) [(1/6)*(60*n^3-72*n^2+18*n): n in [1..40]]; // Vincenzo Librandi, Jul 26 2011

Crossrefs

Cf. A100168 = alternate vertex; A100145 for more on structured numbers.

Sequence in context: A135176 A318625 A281208 * A100168 A137022 A160064

Adjacent sequences: A100164 A100165 A100166 * A100168 A100169 A100170

Keyword

easy,nonn

Author

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

Status

approved