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%I #17 Jun 11 2020 03:17:10
%S 1,1,-1,-1,11,1,-193,-5,3851,449,-16493,-17093,2776513483,2766847,
%T -18326878991,-284903947,313476755027,15306883537,-5759963886461,
%U -549822999679,43471527926977757,649802711643571,-53651420037921807347,-278016083032863199,164833044827776566977996843
%N Define b(n) by 1/sm(w) = Sum_{n >= 0} b(3*n-1)*w^(3*n-1), where sm(w) is the elliptic function defined in A104133; a(n) = numerator of b(3*n-1).
%C Note that the expansions of 1/sm(w) and cm(w)/sm(w) on page 4 of the Adams reference agree apart from signs.
%D Oscar S. Adams, Elliptic Functions Applied to Conformal World Maps, Special Publication No. 112 of the U.S. Coast and Geodetic Survey, 1925. See pp. 3-4.
%e 1/sm(w) = w^(-1) + (1/6)*w^2 - (1/252)*w^5 - (1/4536)*w^8 + (11/2476656)*w^11 + (1/3714984)*w^14 - (193/35574686784)*w^17 - (5/15246294336)*w^20 + (3851/582713369521920)*w^23 + (449/1123804355506560)*w^26 - ...
%o (PARI) anum(nn) = my(A = O(x)); for(i=0, nn, A = intformal( (1 - intformal(A^2))^2) ); my(v=Vec(1/A)); apply(x->numerator(x), vector(#v\3, k, v[3*k-2]));
%Y Cf. A104133 (sm), A104134 (cm), A335158 (denominators).
%Y See also A335180, A335181.
%K sign,frac
%O 0,5
%A _Michel Marcus_ and _N. J. A. Sloane_, Jun 08 2020.
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