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1123+21460n.
1

%I #14 Jul 13 2015 21:33:15

%S 1123,22583,44043,65503,86963,108423,129883,151343,172803,194263,

%T 215723,237183,258643,280103,301563,323023,344483,365943,387403,

%U 408863,430323,451783,473243,494703,516163,537623,559083,580543,602003,623463

%N 1123+21460n.

%C Arises in an important Ramanujan formula for Pi: 4/Pi=1123/882-22583/882^3*(1/2*(1*3)/4^2)+...

%D L. Berggren, J. Borwein and P. Borwein, "Pi: A source book", Springer, second edition, p. 328.

%D S. Ramanujan, "Modular equations and approximations to Pi", Quart. J. Pure Appl. Math., v. 45, 1914, p. 350-372.

%H Harvey P. Dale, <a href="/A069984/b069984.txt">Table of n, a(n) for n = 0..1000</a>

%H Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html">Recursive Sequences</a>

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1).

%F a(0)=1123, a(1)=22583, a(n)=2*a(n-1)-a(n-2). - _Harvey P. Dale_, Feb 04 2015

%t 21460*Range[0,30]+1123 (* or *) LinearRecurrence[{2,-1},{1123,22583},30] (* _Harvey P. Dale_, Feb 04 2015 *)

%K easy,nonn

%O 0,1

%A _Benoit Cloitre_, May 01 2002