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List of pairs n,13*n.
1

%I #18 Oct 16 2019 11:28:12

%S 1,13,2,26,3,39,4,52,5,65,6,78,7,91,8,104,9,117,10,130,11,143,12,156,

%T 13,169,14,182,15,195,16,208,17,221,18,234,19,247,20,260,21,273,22,

%U 286,23,299,24,312,25,325,26,338,27,351,28,364,29,377,30,390,31,403,32,416,33

%N List of pairs n,13*n.

%H Colin Barker, <a href="/A176593/b176593.txt">Table of n, a(n) for n = 1..1000</a>

%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (0,2,0,-1).

%F a(n) = (14*n+12*n*(-1)^n+1 + (-1)^(n-1))/4 for n>1.

%F From _Colin Barker_, Jan 02 2017: (Start)

%F a(n) = 2*a(n-2) - a(n-4) for n>4.

%F G.f.: x*(1+13*x) / ((1-x)^2*(1+x)^2).

%F (End)

%t Table[{n,13n},{n,50}]//Flatten (* or *) LinearRecurrence[{0,2,0,-1},{1,13,2,26},100] (* _Harvey P. Dale_, Oct 16 2019 *)

%o (PARI) Vec(x*(1+13*x) / ((1-x)^2*(1+x)^2) + O(x^30)) \\ _Colin Barker_, Jan 02 2017

%Y Cf. A008595.

%K nonn,tabf,easy

%O 1,2

%A _Vincenzo Librandi_, Apr 23 2010

%E Partially edited by _N. J. A. Sloane_, Jun 23 2010