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%I #9 Nov 12 2014 10:34:02
%S 10,69300,9729720,4257000,967412160,4104100000,1408951239696000,
%T 59860503846000000,1542547619019487080000,39054496014386012160000,
%U 450510331438947780000000
%N Least decagonal (10-gonal) number that is the product of n decagonal numbers greater than 1.
%H Lars Blomberg, <a href="/A225070/a225070.txt">Table of n, a(n) with solutions for n=1..11</a>
%e Let dec(n) = n*(4n-3). Then
%e a(1) = 10 = dec(2).
%e a(2) = 69300 = dec(132) = dec(2) * dec(42).
%e a(3) = 9729720 = dec(1560) = dec(3) * dec(4) * dec(42).
%e a(4) = 4257000 = dec(1032) = dec(2)^3 * dec(33).
%e a(5) = 967412160 = dec(15552) = dec(2) * dec(3) * dec(4) * dec(8) * dec(9).
%e a(6) = 4104100000 = dec(32032) = dec(2)^3 * dec(4) * dec(7) * dec(11).
%Y Cf. A001107 (decagonal numbers).
%Y Cf. A212616, A212617, A225066-A225069 (3-, 5- to 9-gonal cases).
%K nonn,more
%O 1,1
%A _T. D. Noe_, May 01 2013
%E Corrected a(6) and added a(7)-a(11) by _Lars Blomberg_, Sep 20 2013
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