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A195856
a(n) = T(10,n), array T given by A048505.
1
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
0,2
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
MATHEMATICA
LinearRecurrence[{7, -18, 20, -8}, {1, 122, 387, 965}, 30] (* Harvey P. Dale, Dec 29 2014 *)
PROG
(Magma) [(n^2+41*n+400)*2^(n-2)-99: n in [0..30]]
(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
KEYWORD
nonn,easy,less
AUTHOR
Vincenzo Librandi, Sep 25 2011
STATUS
approved