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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
OFFSET
1,2
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
KEYWORD
easy,nonn
AUTHOR
James A. Record (james.record(AT)gmail.com), Nov 07 2004
STATUS
approved