This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A081955 #11 Nov 18 2018 00:41:53
%S A081955 1,2,24,1728,746496,1934917632,30091839012864,2807929681968365568,
%T A081955 1572081206902992767287296,5280985496827154199640037916672,
%U A081955 106440332834866049138191223105387495424,12872079797383178927229037635891253693013557248
%N A081955 a(n) = 2^r*3^s where r = n(n+1)/2 and s = n(n-1)/2.
%F A081955 a(n+1) = 2^(n+1)*3^n*a(n), a(1) = 2. - _Ryan Propper_, Jun 15 2005
%F A081955 A171795(n) = a(-n). a(n+1) * a(n-1) = 6 * a(n)^2. - _Michael Somos_, Dec 17 2009
%t A081955 Do[Print[2^(n*(n+1)/2)*3^(n*(n-1)/2)], {n, 10}] (* _Ryan Propper_, Jun 15 2005 *)
%o A081955 (PARI) {a(n) = 3^(n*(n-1)/2) * 2^(n*(n+1)/2)} /* _Michael Somos_, Dec 17 2009 */
%Y A081955 Sequence contains the product of a row in A081954.
%Y A081955 Cf. A025192, A081954, A081956.
%K A081955 nonn
%O A081955 0,2
%A A081955 _Amarnath Murthy_, Apr 02 2003
%E A081955 More terms from _Ryan Propper_, Jun 15 2005