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A048482 a(n) = T(n,n), array T given by A048472. 3
1, 3, 13, 49, 161, 481, 1345, 3585, 9217, 23041, 56321, 135169, 319489, 745473, 1720321, 3932161, 8912897, 20054017, 44826625, 99614721, 220200961, 484442113, 1061158913, 2315255809, 5033164801, 10905190401, 23555211265, 50734301185, 108984795137 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (7,-18,20,-8).

FORMULA

a(n) = 2 * A001788(n) + 1.

a(n) = (n^2+n)*2^(n-1) + 1. - Ralf Stephan, Sep 02 2003

G.f.: -(8*x^3-10*x^2+4*x-1) / ((x-1)*(2*x-1)^3). - Colin Barker, Nov 26 2014

a(0)=1, a(1)=3, a(2)=13, a(3)=49, a(n)=7*a(n-1)-18*a(n-2)+ 20*a(n-3)- 8*a(n-4). - Harvey P. Dale, Feb 02 2015

MATHEMATICA

LinearRecurrence[{7, -18, 20, -8}, {1, 3, 13, 49}, 30] (* Harvey P. Dale, Feb 02 2015 *)

PROG

(MAGMA) [(n^2+n)*2^(n-1) + 1: n in [0..30]]; // Vincenzo Librandi, Sep 23 2011

(PARI) Vec(-(8*x^3-10*x^2+4*x-1)/((x-1)*(2*x-1)^3) + O(x^100)) \\ Colin Barker, Nov 26 2014

CROSSREFS

Cf. A002999, A003013, A001787, A005183, A001788.

Sequence in context: A122424 A027326 A108946 * A094978 A251743 A178934

Adjacent sequences:  A048479 A048480 A048481 * A048483 A048484 A048485

KEYWORD

nonn,easy

AUTHOR

Clark Kimberling

STATUS

approved

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Last modified July 18 15:37 EDT 2019. Contains 325144 sequences. (Running on oeis4.)