login
A048480
a(n) = T(8,n), array T given by A048472.
1
1, 10, 37, 109, 289, 721, 1729, 4033, 9217, 20737, 46081, 101377, 221185, 479233, 1032193, 2211841, 4718593, 10027009, 21233665, 44826625, 94371841, 198180865, 415236097, 868220929, 1811939329, 3774873601, 7851737089, 16307453953, 33822867457, 70061654017
OFFSET
0,2
FORMULA
a(n) = 9*n * 2^(n-1) + 1.
a(0)=1, a(1)=10, a(2)=37, a(n) = 5*a(n-1)-8*a(n-2)+4*a(n-3). - Harvey P. Dale, Jul 09 2014
G.f.: (1+5*x-5*x^2) / ((1-x)*(1-2*x)^2). - Colin Barker, Feb 18 2016
MATHEMATICA
Table[9*n*2^(n-1)+1, {n, 0, 30}] (* or *) LinearRecurrence[{5, -8, 4}, {1, 10, 37}, 30] (* Harvey P. Dale, Jul 09 2014 *)
PROG
(Magma) [9*n * 2^(n-1) + 1: n in [0..30]]; // Vincenzo Librandi, Sep 23 2011
(PARI) Vec((1+5*x-5*x^2)/((1-x)*(1-2*x)^2) + O(x^40)) \\ Colin Barker, Feb 18 2016
CROSSREFS
Cf. A008591 (contains n-th difference of a(n),a(n-1),...,a(0)).
Cf. A048472.
Sequence in context: A047672 A200872 A212755 * A116970 A355044 A373577
KEYWORD
nonn,easy
STATUS
approved