OFFSET
1,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..1000
Index entries for linear recurrences with constant coefficients, signature (20,-150,500,-625).
FORMULA
a(1)=0, a(2)=100, a(3)=2250, a(4)=30000, a(n)=20*a(n-1)- 150*a(n-2)+ 500*a(n-3)- 625*a(n-4). - Harvey P. Dale, Oct 25 2011
G.f.: (50*(5*x^2+2*x))/(5*x-1)^4. - Harvey P. Dale, Oct 25 2011
MATHEMATICA
Table[(n^3-n^2)5^n, {n, 20}] (* or *) LinearRecurrence[{20, -150, 500, -625}, {0, 100, 2250, 30000}, 20]
PROG
(Magma) [(n^3-n^2)*5^n: n in [1..30]]; // Vincenzo Librandi, Oct 26 2011
CROSSREFS
KEYWORD
nonn
AUTHOR
Mohammad K. Azarian, Apr 30 2007
EXTENSIONS
Offset corrected by Mohammad K. Azarian, Nov 19 2008
STATUS
approved