login
A100174
Structured tetrakis hexahedral numbers (vertex structure 5).
3
1, 14, 59, 156, 325, 586, 959, 1464, 2121, 2950, 3971, 5204, 6669, 8386, 10375, 12656, 15249, 18174, 21451, 25100, 29141, 33594, 38479, 43816, 49625, 55926, 62739, 70084, 77981, 86450, 95511, 105184
OFFSET
1,2
FORMULA
a(n) = (1/6)*(20*n^3 - 24*n^2 + 10*n).
G.f.: x*(1+x)*(1+9*x)/(1-x)^4. [Colin Barker, May 29 2012]
PROG
(Magma) [(1/6)*(20*n^3-24*n^2+10*n): n in [1..50] ]; // Vincenzo Librandi, Aug 02 2011
CROSSREFS
Cf. A005915 = alternate vertex; cf. A100145 for more on structured numbers.
Sequence in context: A084195 A033856 A143861 * A372675 A120371 A062022
KEYWORD
easy,nonn
AUTHOR
James A. Record (james.record(AT)gmail.com), Nov 07 2004
EXTENSIONS
Formula corrected by Helena Verrill (verrill(AT)math.lsu.edu), Mar 23 2007
STATUS
approved