A100168 Structured pentagonal icositetrahedral numbers (vertex structure 10).

1, 38, 174, 472, 995, 1806, 2968, 4544, 6597, 9190, 12386, 16248, 20839, 26222, 32460, 39616, 47753, 56934, 67222, 78680, 91371, 105358, 120704, 137472, 155725, 175526, 196938, 220024, 244847, 271470, 299956, 330368

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) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4); a(1)=1, a(2)=38, a(3)=174, a(4)=472. - Harvey P. Dale, Dec 18 2011

G.f.: (28*x^2 + 34*x + 1)/(x-1)^4. - Harvey P. Dale, Dec 18 2011

Mathematica

Table[(63n^3-81n^2+24n)/6, {n, 40}]
LinearRecurrence[{4, -6, 4, -1}, {1, 38, 174, 472}, 40] (* or *) CoefficientList[ Series[(1+34x+28x^2)/(-1+x)^4, {x, 0, 40}], x](* Harvey P. Dale, Dec 18 2011 *)

Prog

(Magma) [(1/6)*(63*n^3-81*n^2+24*n): n in [1..40]]; // Vincenzo Librandi, Jul 26 2011

Crossrefs

Cf. A100167 = alternate vertex; A100145 for more on structured numbers.

Sequence in context: A318625 A281208 A100167 * A137022 A160064 A297541

Adjacent sequences: A100165 A100166 A100167 * A100169 A100170 A100171

Keyword

easy,nonn

Author

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

Status

approved