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 A341874 #8 Feb 25 2021 08:28:49
%S A341874 1,-6,8118,1740636,937783902,364856395608,172736345164500,
%T A341874 78278100914583312,37268001893898954198,17773741638825114790854,
%U A341874 8624927270409695050736952,4214914849580580859932456300,2078204723099375850950863499028
%N A341874 Coefficients of the series whose 24th power equals E_2(x)^7/E_14(x), where E_2(x) and E_14(x) are the Eisenstein series A006352 and A058550.
%C A341874 It is easy to see that E_2(x)^7/E_14(x) == 1 - 24*Sum_{k >= 1} (7*k - 11*k^13)*x^k/(1 - x^k) (mod 144), and also that the integer 7*k - k^13 is always divisible by 6. Hence, E_2(x)^7/E_14(x) == 1 (mod 144). It follows from Heninger et al., p. 3, Corollary 2, that the series expansion of (E_2(x)^7/E_14(x))^(1/24) = 1 - 6*x + 8118*x^2 + 1740636*x^3 + 937783902*x^4 + ... has integer coefficients.
%H A341874 N. Heninger, E. M. Rains and N. J. A. Sloane, <a href="https://doi.org/10.1016/j.jcta.2006.03.018">On the Integrality of n-th Roots of Generating Functions</a>, J. Combinatorial Theory, Series A, 113 (2006), 1732-1745.
%H A341874 Wikipedia, <a href="https://en.wikipedia.org/wiki/Eisenstein_series">Eisenstein series</a>
%p A341874 E(2,x) := 1 - 24*add(k*x^k/(1-x^k), k = 1..20):
%p A341874 E(14,x) := 1 - 24*add(k^13*x^k/(1-x^k), k = 1..20):
%p A341874 with(gfun): series((E(2,x)^7/E(14,x))^(1/24), x, 20):
%p A341874 seriestolist(%);
%Y A341874 Cf. A006352, A058550, A341871 - A341875.
%K A341874 sign,easy
%O A341874 0,2
%A A341874 _Peter Bala_, Feb 23 2021