A078501 - OEIS

%I #6 Mar 30 2012 18:39:11

%S 1,7,26,78,211,537,1312,3112,7217,16443,36934,82002,180319,393325,

%T 852092,1835148,3932317,8388783,17825986,37748950,79692011,167772417,

%U 352321816,738197808,1543504201,3221225827,6710886782,13958644122

%N a(n) = sum(k=1,n^2, A078446(k)).

%F a(n) = 2*(n-2)*2^n + n*(n+1)/2 + 4

%F G.f.: x*(1-4*x^2+4*x^3)/((2*x-1)^2 * (1-x)^3) [From Maksym Voznyy (voznyy(AT)mail.ru), Jul 27 2009]

%o (PARI) a(n)=2*(n-2)*2^n +n*(n+1)/2+4

%K nonn

%O 1,2

%A _Benoit Cloitre_, Jan 04 2003

%E G.f. proposed by Maksym Voznyy checked and corrected by R. J. Mathar, Sep 16 2009.