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 A266773 #8 Sep 08 2022 08:46:15
%S A266773 1,1,2,3,5,8,12,17,25,35,49,66,90,119,158,206,267,342,437,551,694,865,
%T A266773 1074,1324,1627,1985,2414,2919,3518,4219,5045,6003,7125,8422,9927,
%U A266773 11660,13660,15949,18578,21575,24998,28884,33303,38298,43955,50329,57513,65581,74645,84786
%N A266773 Molien series for invariants of finite Coxeter group D_10 (bisected).
%C A266773 The Molien series for the finite Coxeter group of type D_k (k >= 3) has G.f. = 1/Prod_i (1-x^(1+m_i)) where the m_i are [1,3,5,...,2k-3,k-1]. If k is even only even powers of x appear, and we bisect the sequence.
%D A266773 J. E. Humphreys, Reflection Groups and Coxeter Groups, Cambridge, 1990. See Table 3.1, page 59.
%H A266773 G. C. Greubel, <a href="/A266773/b266773.txt">Table of n, a(n) for n = 0..1000</a>
%H A266773 <a href="/index/Mo#Molien">Index entries for Molien series</a>
%F A266773 G.f.: 1/((1-t^2)*(1-t^4)*(1-t^6)*(1-t^8)*(1-t^10)^2*(1-t^12)*(1-t^14)*(1-t^16)*(1-t^18)), bisected.
%F A266773 G.f.: 1/( (1-x^5)*(Product_{j=1..9} 1-x^j) ). - _G. C. Greubel_, Feb 03 2020
%p A266773 seq(coeff(series(1/((1-x^5)*mul(1-x^j, j=1..9)), x, n+1), x, n), n = 0..50); # _G. C. Greubel_, Feb 03 2020
%t A266773 CoefficientList[Series[1/((1-x^5)*Product[1-x^j, {j,9}]), {x,0,50}], x] (* _G. C. Greubel_, Feb 03 2020 *)
%o A266773 (PARI) Vec(1/((1-x^5)*prod(j=1,9,1-x^j)) +O('x^50)) \\ _G. C. Greubel_, Feb 03 2020
%o A266773 (Magma) R<x>:=PowerSeriesRing(Integers(), 50); Coefficients(R!( 1/((1-x^5)*(&*[1-x^j: j in [1..9]])) )); // _G. C. Greubel_, Feb 03 2020
%o A266773 (Sage)
%o A266773 def A266773_list(prec):
%o A266773 P.<x> = PowerSeriesRing(ZZ, prec)
%o A266773 return P( 1/((1-x^5)*product(1-x^j for j in (1..9))) ).list()
%o A266773 A266773_list(50) # _G. C. Greubel_, Feb 03 2020
%Y A266773 Molien series for finite Coxeter groups D_3 through D_12 are A266755, A266769, A266768, A003402, and A266770-A266775.
%K A266773 nonn
%O A266773 0,3
%A A266773 _N. J. A. Sloane_, Jan 11 2016