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A100173
Structured pentakis dodecahedral numbers (vertex structure 6).
2
1, 32, 148, 404, 855, 1556, 2562, 3928, 5709, 7960, 10736, 14092, 18083, 22764, 28190, 34416, 41497, 49488, 58444, 68420, 79471, 91652, 105018, 119624, 135525, 152776, 171432, 191548, 213179, 236380, 261206, 287712
OFFSET
1,2
FORMULA
a(n) = (1/6)*(55*n^3 - 75*n^2 + 26*n).
G.f.: x*(1 + 28*x + 26*x^2)/(1-x)^4. - Colin Barker, May 29 2012
MATHEMATICA
LinearRecurrence[{4, -6, 4, -1}, {1, 32, 148, 404}, 40] (* Harvey P. Dale, Aug 04 2022 *)
PROG
(Magma) [(1/6)*(55*n^3-75*n^2+26*n): n in [1..40]]; // Vincenzo Librandi, Jul 26 2011
CROSSREFS
Cf. A100165 = alternate vertex; A100145 for more on structured numbers.
Sequence in context: A228758 A097199 A100165 * A234874 A220975 A100172
KEYWORD
easy,nonn
AUTHOR
James A. Record (james.record(AT)gmail.com), Nov 07 2004
STATUS
approved