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A100168 Structured pentagonal icositetrahedral numbers (vertex structure 10). 2
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified June 14 01:29 EDT 2021. Contains 345016 sequences. (Running on oeis4.)