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Revision History for A000521

(Underlined text is an addition; strikethrough text is a deletion.)

Showing entries 1-10 | older changes
A000521 Coefficients of modular function j as power series in q = e^(2 Pi i t). Another name is the elliptic modular invariant J(tau).
(history; published version)
#254 by N. J. A. Sloane at Mon Jul 01 12:53:27 EDT 2024
STATUS

editing

approved

#253 by N. J. A. Sloane at Mon Jul 01 12:53:25 EDT 2024
LINKS

John Cremona, <a href="httphttps://www.maths.nott.ac.uk/personal/jec">Home page</a>

STATUS

approved

editing

#252 by Michel Marcus at Mon Feb 26 01:27:50 EST 2024
STATUS

reviewed

approved

#251 by Joerg Arndt at Mon Feb 26 01:15:16 EST 2024
STATUS

proposed

reviewed

#250 by Joerg Arndt at Mon Feb 26 01:15:13 EST 2024
STATUS

editing

proposed

#249 by Joerg Arndt at Mon Feb 26 01:15:02 EST 2024
MATHEMATICA

a[n_] := SeriesCoefficient[ 12^3 KleinInvariantJ[Log[q]/(2 Pi I)], )], {q, 0, n}] (* _Leo C. Stein_, Feb 25 2024 *)

{q, 0, n}] (* Leo C. Stein, Feb 25 2024 *)

STATUS

proposed

editing

Discussion
Mon Feb 26 01:15
Joerg Arndt: thanks!
#248 by Leo C. Stein at Mon Feb 26 00:53:26 EST 2024
STATUS

editing

proposed

#247 by Leo C. Stein at Mon Feb 26 00:49:16 EST 2024
MATHEMATICA

a[n_] := SeriesCoefficient[With[{L = InverseEllipticNomeQ[Sqrt[q]]}, rootQ]}, 256 (L^2 - L + 1)^3/(L (1 - L))^2], {qrootQ, 0, n2n}]; (* Jan Mangaldan, Jul 07 2020, after _Michael Somos_ *)_; corrected by _Leo C. Stein_, Feb 25 2024 *)

a[n_] := SeriesCoefficient[ 12^3 KleinInvariantJ[Log[q]/(2 Pi I)],

{q, 0, n}] (* Leo C. Stein, Feb 25 2024 *)

STATUS

approved

editing

Discussion
Mon Feb 26 00:52
Leo C. Stein: There seems to be a Mathematica bug that made the function by Jan Mangaldan incorrect (the math itself is correct, but Mathematica gave an incorrect result starting with a(3)). This was corrected by avoiding the square root in his function. At the same time I added the most native approach I could write in Mathematica.
#246 by N. J. A. Sloane at Mon Sep 18 13:15:21 EDT 2023
STATUS

editing

approved

#245 by N. J. A. Sloane at Mon Sep 18 13:15:18 EDT 2023
REFERENCES

Evans, David E., and Yasuyuki Kawahigashi. "Subfactors and mathematical physics." Bulletin of the American Mathematical Society, 60:4, (2023), 459-482 (see page 472).

STATUS

approved

editing

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Last modified September 7 04:49 EDT 2024. Contains 375729 sequences. (Running on oeis4.)