OFFSET
1,1
COMMENTS
(A166911=3,13,39,89,171,293,). 5 formulas for a(n):fifth is a(n)=4a(n-1)-6a(n-2)+4a(n-3)-a(n-4), a(0)=16,a(1)=128,a(2)=464,a(3)=1152. See A166464 and its companion A166911 (offset 0). Note, for a(n) mod 10, period 5:repeat 6,8,4,2,0. Mathematically, a(n) (then A100178=1,8,29,72,145,) can be preceded by 0.
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..10000
FORMULA
a(n) = 16*n*(2-3*n+4*n^2)/3 = 16*(2*n-3*n^2+4*n^3)/3 = 16*A100178(n).
MATHEMATICA
Table[16*n*(2 - 3*n + 4*n^2)/3, {n, 1, 50}] (* G. C. Greubel, Jun 13 2016 *)
PROG
(Magma) [16*n*(2-3*n+4*n^2)/3: n in [1..40]]; // Vincenzo Librandi, Aug 03 2011
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Paul Curtz, Nov 04 2009
STATUS
approved