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 A225066 #7 Sep 21 2013 07:28:56 %S A225066 6,2850,79800,2162160,134734320,15518903400,174626020800, %T A225066 19794628854000,659394533191680,659394533191680,659394533191680, %U A225066 38022361747469489295360 %N A225066 Least hexagonal number that is the product of n hexagonal numbers greater than 1. %H A225066 Lars Blomberg, <a href="/A225066/a225066.txt">Table of n, a(n) with solutions for n=1..12</a> %e A225066 Let hex(n) = n*(2n-1). Then %e A225066 a(1) = 6 = hex(2). %e A225066 a(2) = 2850 = hex(38) = hex(3) * hex(10). %e A225066 a(3) = 79800 = hex(200) = hex(3) * hex(4) * hex(10). %e A225066 a(4) = 2162160 = hex(1040) = hex(2)^2 * hex(4) * hex(33). %e A225066 a(5) = 134734320 = hex(8208) = hex(2)^2 * hex(3) * hex(4) * hex(67). %e A225066 a(6) = 15518903400 = hex(88088) = hex(2) * hex(3) * hex(6)^2 * hex(7) * hex(15). %Y A225066 Cf. A000384 (hexagonal numbers). %Y A225066 Cf. A212616, A212617, A225066-A225070 (3-, 5- to 10-gonal cases). %K A225066 nonn,more %O A225066 1,1 %A A225066 _T. D. Noe_, May 01 2013 %E A225066 Corrected a(6) and added a(7)-a(12) by _Lars Blomberg_, Sep 21 2013