A026972 - OEIS

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A026972

a(n) = Sum_{k=0..n-1} T(n,k) * T(n,k+1), with T given by A026648.

%I #8 Oct 20 2019 18:39:46

%S 1,6,24,108,406,1908,7289,34248,131766,623700,2416836,11487528,

%T 44745468,213451560,834897375,3993910416,15673923910,75152083716,

%U 295737641768,1420670333640,5603322265428,26960309526744,106539505068194,513309625743600,2031786103702780,9800639852315208

%N a(n) = Sum_{k=0..n-1} T(n,k) * T(n,k+1), with T given by A026648.

%K nonn

%O 1,2

%A _Clark Kimberling_

%E More terms from _Sean A. Irvine_, Oct 20 2019