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A100162
Structured disdyakis dodecahedral numbers (vertex structure 7).
4
1, 26, 117, 316, 665, 1206, 1981, 3032, 4401, 6130, 8261, 10836, 13897, 17486, 21645, 26416, 31841, 37962, 44821, 52460, 60921, 70246, 80477, 91656, 103825, 117026, 131301, 146692, 163241, 180990, 199981, 220256
OFFSET
1,2
COMMENTS
Also structured deltoidal icositetrahedral numbers (vertex structure 7) (cf. A100161 = alternate vertex).
LINKS
FORMULA
a(n) = (1/6)*(42*n^3 - 54*n^2 + 18*n).
G.f.: x*(1 + 22*x + 19*x^2)/(1-x)^4. - Colin Barker, Jan 19 2012
PROG
(Magma) [(1/6)*(42*n^3-54*n^2+18*n): n in [1..40]]; // Vincenzo Librandi, Jul 24 2011
CROSSREFS
Cf. A100161, A100163 = alternate vertices; A100145 for more on structured polyhedral numbers.
Cf. A260260 (comment). - Bruno Berselli, Jul 22 2015
Sequence in context: A251262 A221570 A100161 * A051729 A100163 A296325
KEYWORD
nonn,easy
AUTHOR
James A. Record (james.record(AT)gmail.com), Nov 07 2004
STATUS
approved