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a(n) = Sum_{k=0..n} C(2n,k)*A126155(n,k).
1

%I #7 Jan 25 2020 00:47:48

%S 1,12,624,72768,15073536,4879690752,2275446779904,1444596033404928,

%T 1198103353905709056,1257795823373397000192,1630379271356490615619584,

%U 2557344389023281412086693888,4774145871907749099664809394176

%N a(n) = Sum_{k=0..n} C(2n,k)*A126155(n,k).

%F a(n) = 4^n*Sum_{k=0..n} 2^(n-k)*3^k*A088874(n,k). - _Philippe Deléham_, Dec 21 2006

%e a(1) = 1*(1) + 2*(5) + 1*(1) = 12;

%e a(2) = 1*(7) + 4*(35) + 6*(55) + 4*(35) + 1*(7) = 624;

%e a(3) = 1*(139) + 6*(695) + 15*(1195) + 20*(1415) + 15*(1195) + 6*(695) + 1*(139) = 72768.

%Y Cf. A126155.

%K nonn

%O 0,2

%A _Paul D. Hanna_, Dec 20 2006