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A100159
Structured disdyakis triacontahedral numbers (vertex structure 7).
4
1, 62, 297, 820, 1745, 3186, 5257, 8072, 11745, 16390, 22121, 29052, 37297, 46970, 58185, 71056, 85697, 102222, 120745, 141380, 164241, 189442, 217097, 247320, 280225, 315926, 354537, 396172, 440945, 488970, 540361, 595232
OFFSET
1,2
COMMENTS
Also structured deltoidal hexacontahedral numbers (vertex structure 7) (cf. A100158, A100166 = alternate vertices).
LINKS
FORMULA
a(n) = (1/6)*(114*n^3 - 162*n^2 + 54*n) = n*(19*n^2 - 27*n + 9).
G.f.: x*(1 + 58*x + 55*x^2)/(1-x)^4. [Colin Barker, Apr 16 2012]
PROG
(Magma) [(1/6)*(114*n^3-162*n^2+54*n): n in [1..40]]; // Vincenzo Librandi, Jul 19 2011
CROSSREFS
Cf. A100158, A100160 = alternate vertices; A100145 for more on structured polyhedral numbers.
Sequence in context: A045220 A100158 A100166 * A100160 A223072 A010746
KEYWORD
nonn,easy
AUTHOR
James A. Record (james.record(AT)gmail.com), Nov 07 2004
STATUS
approved