A075634 - OEIS

%I #5 Dec 05 2013 19:55:39

%S 1,2,5,18,98,306,9378,1726173,13347339101,321699559882750173,

%T 4716070968330003553938242926173,

%U 23987291841663781653328392594255840802707701158676395298

%N Final terms of groups in A075631.

%F a(n) = A075633(n+1) - 1. Also, a(n) = (sqrt(8*(A075631(1) + A075631(2) + ... + A075631(n)) + 1) - 1) / 2. [From _Max Alekseyev_, May 08 2009]

%Y Cf. A075631, A075632, A075633.

%K nonn

%O 1,2

%A _Amarnath Murthy_, Sep 30 2002

%E More terms from Jonathan Cross (jcross(AT)juggler.net), May 08 2004

%E One more term from _Max Alekseyev_, May 08 2009