A123311 - OEIS

%I #6 Jan 13 2025 04:10:19

%S 1,2,18,336,10050,423576,23317042,1595336448,131036683554,

%T 12595263510000,1389395816978554,173214827643727872,

%U 24105386508556401906,3706800170875348334480,624528505602985043491650

%N Central terms of triangle A123305.

%C Triangle T=A123305 is defined by: (column k of T) = (k+1)*(column k of T^2) shifted to have an initial '1'; thus A123312(n) = a(n)/(n+1) is an integer for n>=0.

%Y Cf. A123305; A123306, A123307, A123308, A123309, A123310, A123312.

%K nonn,more

%O 0,2

%A _Paul D. Hanna_, Sep 25 2006