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 A055978 #8 Apr 30 2014 01:34:06
%S A055978 1,-2,0,4,-24,36,0,-64,252,-290,0,396,-1472,1380,0,-944,4830,-4248,0,
%T A055978 -1268,-6048,8040,0,12528,-16744,-3706,0,-20976,84480,-31284,0,-31312,
%U A055978 -113643,101542,0,152892,-115920,-104792,0,-96576,534612,-112914,0,-369544,-370944,334864,0,603936,-577738,-22554,0
%N A055978 A sequence related to Ramanujan's tau function.
%D A055978 Eichler and Zagier, The Theory of Jacobi Forms, Birkhauser, 1985.
%F A055978 a(4*n + 2) = 0, a(4*n) = A000594(n) (Ramanujan tau(n)).
%F A055978 Sum_{k>0} a(4*k + 1) * q^(4*k + 1) = (-1) * (q * d/dq theta_2(q^4)) * eta(q^4)^18 * eta(q^16)^2 / eta(q^8). - _Michael Somos_, Mar 20 2004
%F A055978 Sum_{k>0} a(4*k + 3) * q^(4*k + 3) = (1/2) * (q * d/dq theta_3(q^4)) * eta(q^4)^16 * eta(q^8)^5 / eta(q^16)^2. - _Michael Somos_, Mar 20 2004
%F A055978 G.f.: x^3 * (Product_{k>0} (1 - x^k) * (1 - x^(4*k))^18 / (1 + x^k)) * (Sum_{k>0} k^2 * x^(k^2)). - _Michael Somos_, Mar 20 2004
%F A055978 phi_{10, 1}*q*(d/dq){theta_3(z)} where phi_{10, 1} is unique Jacobi cusp form of weight 10 index 1 given by A003784.
%e A055978 q^4 - 2*q^5 + 4*q^7 - 24*q^8 + 36*q^9 - 64*q^11 + 252*q^12 - 290*q^13 + ...
%o A055978 (PARI) {a(n) = local(A); if( n<3, 0, n-=3; A = x * O(x^n); polcoeff( eta(x + A)^2 * eta(x^4 + A)^18 / eta(x^2 + A) * sum( k=1, sqrtint(n), k^2 * x^(k^2)), n))} /* _Michael Somos_, Mar 20 2004 */
%Y A055978 A003784, A000594.
%K A055978 sign
%O A055978 4,2
%A A055978 Kok Seng Chua (chuaks(AT)ihpc.nus.edu.sg), Jul 24 2000