A195856 a(n) = T(10,n), array T given by A048505.

1, 122, 387, 965, 2221, 4941, 10813, 23453, 50589, 108701, 232861, 497565, 1060765, 2256797, 4792221, 10157981, 21495709, 45416349, 95813533, 201850781, 424673181, 892338077, 1872756637, 3925868445, 8220835741, 17196646301

Offset: 0

Author

Vincenzo Librandi, Sep 25 2011

Keywords

• nonn
• easy
• less

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..2000
• Index entries for linear recurrences with constant coefficients, signature (7,-18,20,-8).

Crossrefs

Cf. A048506, A048507, A048508, A048509, A048510, A048511, A048512, A048513, A048514, A048515, A195855.

Programs

Magma

[(n^2+41*n+400)*2^(n-2)-99: n in [0..30]]

Mathematica

LinearRecurrence[{7,-18,20,-8},{1,122,387,965},30] (* Harvey P. Dale, Dec 29 2014 *)

PARI

a(n)=(n^2+41*n+400)<<(n-2)-99 \\ Charles R Greathouse IV, Dec 27 2011

PARI

Vec((432*x^3-449*x^2+115*x+1) / ((x-1)*(2*x-1)^3) + O(x^100)) \\ Colin Barker, Feb 25 2015

Formula

a(n) = (n^2+41*n+400)*2^(n-2)-99.

a(n) = 7*a(n-1)-18*a(n-2)+20*a(n-3)-8*a(n-4). - Colin Barker, Feb 25 2015

G.f.: (432*x^3-449*x^2+115*x+1) / ((x-1)*(2*x-1)^3). Colin Barker, Feb 25 2015