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A282017 Coefficients in q-expansion of (E_4 + E_2^2)/2, where E_2 and E_4 are the Eisenstein series shown in A006352 and A004009, respectively.

%I A282017 #12 Feb 05 2017 01:36:45
%S A282017 1,96,1296,4992,13488,25920,50112,74496,123120,164832,246240,300672,
%T A282017 442176,501312,694656,794880,1052016,1135296,1534032,1591680,2086560,
%U A282017 2214912,2763072,2840832,3723840,3668640,4590432,4750080,5801088,5728320,7309440,7007232,8697456,8722944,10349856,10160640
%N A282017 Coefficients in q-expansion of (E_4 + E_2^2)/2, where E_2 and E_4 are the Eisenstein series shown in A006352 and A004009, respectively.
%p A282017 with(numtheory); M:=100;
%p A282017 E := proc(k) local n, t1; global M;
%p A282017 t1 := 1-(2*k/bernoulli(k))*add(sigma[k-1](n)*q^n, n=1..M+1);
%p A282017 series(t1, q, M+1); end;
%p A282017 e2:=E(2); e4:=E(4); e6:=E(6);
%p A282017 series((e2^2+e4)/2,q,M+1);
%p A282017 seriestolist(%);
%Y A282017 Cf. A004009 and A006352.
%K A282017 nonn
%O A282017 0,2
%A A282017 _N. J. A. Sloane_, Feb 05 2017