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%I #12 Aug 31 2021 04:38:22
%S 1,6,15,36,77,162,327,648,1262,2430,4629,8748,16414,30618,56819,
%T 104976,193187,354294,647747,1180980,2147793,3897234,7057034,12754584,
%U 23012070,41452398,74559107,133923132,240246014,430467210,770444114,1377495072
%N a(n) = floor(n*3^(n/2)).
%F a(n) = A128444(n,n).
%p seq(floor(evalf(n*3^(n/2))), n=1..32); # _Georg Fischer_, Aug 31 2021
%o (PARI) a(n) = sqrtint(n^2*3^n); \\ _Michel Marcus_, Aug 31 2021
%Y Cf. A128444.
%K nonn,easy
%O 1,2
%A _Clark Kimberling_, Mar 03 2007
%E a(24) and more terms corrected by _Georg Fischer_, Aug 31 2021