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A289305 Expansion of (q*j(q))^(11/24) where j(q) is the elliptic modular invariant (A000521). 17

%I #22 Mar 06 2018 18:00:16

%S 1,341,21527,-244112,50791235,-6177875286,883458515093,

%T -136541356378141,22354744100161913,-3821528558157433970,

%U 675604462786881129711,-122689458583136157060647,22774615293799045532223797

%N Expansion of (q*j(q))^(11/24) where j(q) is the elliptic modular invariant (A000521).

%C In general, the expansion of (q*j(q))^m, where j(q) is the elliptic modular invariant (A000521) and m <> 0, is asymptotic to exp(4*Pi*sqrt(m*n)) * m^(1/4) / (sqrt(2) * n^(3/4)) if 3*m is the positive integer, else is asymptotic to (-1)^n * 3^(3*m) * Gamma(1/3)^(18*m) * exp(Pi*sqrt(3)*(n-m)) / (2^(3*m) * Pi^(12*m) * Gamma(-3*m) * n^(3*m + 1)). - _Vaclav Kotesovec_, Mar 06 2018

%H Seiichi Manyama, <a href="/A289305/b289305.txt">Table of n, a(n) for n = 0..426</a>

%F G.f.: Product_{n>=1} (1-q^n)^(11*A192731(n)/24).

%F a(n) ~ (-1)^n * c * exp(Pi*sqrt(3)*n) / n^(19/8), where c = 0.3243413869190225417519777558769755719610962636852073820509897134587... = 11 * 3^(19/8) * sqrt(2 + sqrt(2)) * Gamma(1/3)^(33/4) * Gamma(3/8) / (2^(67/8) * exp(11 * Pi / (8 * sqrt(3))) * Pi^(13/2)). - _Vaclav Kotesovec_, Jul 03 2017, updated Mar 06 2018

%t CoefficientList[Series[(65536 + x*QPochhammer[-1, x]^24)^(11/8) / (2*QPochhammer[-1, x])^11, {x, 0, 20}], x] (* _Vaclav Kotesovec_, Sep 23 2017 *)

%t (q*1728*KleinInvariantJ[-Log[q]*I/(2*Pi)])^(11/24) + O[q]^13 // CoefficientList[#, q]& (* _Jean-François Alcover_, Nov 02 2017 *)

%Y (q*j(q))^(k/24): A106205 (k=1), A289297 (k=2), A289298 (k=3), A289299 (k=4), A289300 (k=5), A289301 (k=6), A289302 (k=7), A007245 (k=8), A289303 (k=9), A289304 (k=10), this sequence (k=11), A161361 (k=12).

%Y Cf. A000521, A192731.

%K sign

%O 0,2

%A _Seiichi Manyama_, Jul 02 2017

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