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 A138333 #6 Sep 08 2022 08:45:33 %S A138333 -256,3072,-19712,90112,-329472,1025024,-2818816,7028736,-16180736, %T A138333 34850816,-70946304,137592832,-255836672,458422272,-794962432, %U A138333 1338884096,-2196606720,3519493120,-5519205120,8487198720,-12819206400,19045678080,-27869287680 %N A138333 C(n+9, 9)*(n+5)*(-1)^(n+1)*256/5. %C A138333 Sixth column of the triangle defined in A123588, eleventh column of the triangle defined in A123583. %H A138333 <a href="/index/Ch#Cheby">Index entries for sequences related to Chebyshev polynomials.</a> %F A138333 a(n) = coefficient of x^10 in the polynomial 1 - T_(n+5)(x)^2, where T_n(x) is the n-th Chebyshev polynomial of the first kind. %F A138333 G.f.: 256*(x-1)/(x+1)^11. %F A138333 a(n) = (-1)^(n+1)*256*A054334(n). %o A138333 (Magma) [ Binomial(n+9, 9)*(n+5)*(-1)^(n+1)*256/5: n in [0..22] ]; %o A138333 (Magma) k:=5; [ Coefficients(1-ChebyshevT(n+k)^2)[2*k+1]: n in [0..22] ]; %o A138333 (PARI) for(n=0,22,print1(polcoeff(taylor(256*(x-1)/(x+1)^11,x),n),",")); %Y A138333 Cf. A007318 (Pascal's triangle), A123588, A123583, A054334. %K A138333 sign %O A138333 0,1 %A A138333 _Klaus Brockhaus_, Mar 15 2008