OFFSET
0,2
COMMENTS
n-th difference of a(n), a(n-1), ..., a(0) is (5, 6, 7, ...).
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..3000
Index entries for linear recurrences with constant coefficients, signature (5,-8,4).
FORMULA
Main diagonal of the array defined by T(0, j)=j+1 j>=0, T(i, 0)=i+1 i>=0, T(i, j)=T(i-1, j-1)+T(i-1, j)+ 3; a(n)=2^(n-1)*(n+8)-3. - Benoit Cloitre, Jun 17 2003
a(0)=1, a(1)=6, a(2)=17, a(n) = 5*a(n-1) -8*a(n-2) +4*a(n-3). - Vincenzo Librandi, Sep 28 2011
G.f.: (1+x-5*x^2) / ((1-x)*(1-2*x)^2). - Colin Barker, Feb 17 2016
PROG
(Magma) [2^(n-1)*(n+8)-3: n in [0..30]]; // Vincenzo Librandi, Sep 28 2011
(PARI) Vec((1+x-5*x^2)/((1-x)*(1-2*x)^2) + O(x^40)) \\ Colin Barker, Feb 17 2016
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved