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A300052
Coefficients in expansion of (E_4^3/E_6^2)^(1/6).
19
1, 288, 76032, 33042816, 14318032896, 6651157620672, 3146793694792704, 1522045714678435584, 745464270665241870336, 369134048335617435664800, 184269983601798163049283072, 92610644166133510115124717696
OFFSET
0,2
LINKS
FORMULA
Convolution inverse of A299860.
a(n) ~ 2^(4/3) * Pi * exp(2*Pi*n) / (3^(1/6) * Gamma(1/4)^(4/3) * Gamma(1/3) * n^(2/3)). - Vaclav Kotesovec, Mar 04 2018
a(n) * A299860(n) ~ -exp(4*Pi*n) / (2*sqrt(3)*Pi*n^2). - Vaclav Kotesovec, Mar 04 2018
MATHEMATICA
terms = 12;
E4[x_] = 1 + 240*Sum[k^3*x^k/(1 - x^k), {k, 1, terms}];
E6[x_] = 1 - 504*Sum[k^5*x^k/(1 - x^k), {k, 1, terms}];
(E4[x]^3/E6[x]^2)^(1/6) + O[x]^terms // CoefficientList[#, x]& (* Jean-François Alcover, Feb 28 2018 *)
CROSSREFS
(E_4^3/E_6^2)^(k/288): A289365 (k=1), A299694 (k=2), A299696 (k=3), A299697 (k=4), A299698 (k=6), A299943 (k=8), A299949 (k=9), A289369 (k=12), A299950 (k=16), A299951 (k=18), A299953 (k=24), A299993 (k=32), A299994 (k=36), this sequence (k=48), A300053 (k=72), A300054 (k=96), A300055 (k=144), A289209 (k=288).
Cf. A004009 (E_4), A013973 (E_6), A299860.
Sequence in context: A163007 A268873 A069329 * A037946 A282102 A159299
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Feb 23 2018
STATUS
approved