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%I #12 Apr 30 2014 08:07:22
%S 1,1,1,6,160,13125,2544696,978839680,662561095680,724201891583625,
%T 1198933986250000000,2861518844725337212416,9468599329204035806822400,
%U 42083045149004715366557171125,244738882349978781346230604032000,1821980763196818488550000000000000000
%N a(n) = pg(3, n) * pg(4, n) * ... * pg(n, n) where pg(m, n) is the n-th m-th-order polygonal number.
%H Alois P. Heinz, <a href="/A241453/b241453.txt">Table of n, a(n) for n = 0..100</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Polygonal_number">Polygonal number</a>
%e a(5) = pg(3, 5) * pg(4, 5) * pg(5, 5) = 15 * 25 * 35 = 13125.
%p p:= (s, n)-> (n^2*(s-2)-n*(s-4))/2:
%p a:= n-> mul(p(i, n), i=3..n):
%p seq(a(n), n=0..15); # _Alois P. Heinz_, Apr 23 2014
%o (PARI) pg(m, n) = (n^2*(m-2)-n*(m-4))/2;
%o v=[]; for(n=0, 20, v=concat(v, prod(m=3, n, pg(m, n)))); v
%Y Cf. A241452.
%K nonn
%O 0,4
%A _Colin Barker_, Apr 22 2014
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