Properties

Label 16.64.2.a.1
Level $16$
Index $64$
Genus $2$
Analytic rank $2$
Cusps $4$
$\Q$-cusps $0$

Related objects

Downloads

Learn more

Invariants

Level: $16$ $\SL_2$-level: $16$ Newform level: $256$
Index: $64$ $\PSL_2$-index:$64$
Genus: $2 = 1 + \frac{ 64 }{12} - \frac{ 8 }{4} - \frac{ 1 }{3} - \frac{ 4 }{2}$
Cusps: $4$ (none of which are rational) Cusp widths $16^{4}$ Cusp orbits $4$
Elliptic points: $8$ of order $2$ and $1$ of order $3$
Analytic rank: $2$
$\Q$-gonality: $2$
$\overline{\Q}$-gonality: $2$
Rational cusps: $0$
Rational CM points: yes $\quad(D =$ $-3,-11,-19,-27,-43,-67,-163$)

Other labels

Cummins and Pauli (CP) label: 16G2
Rouse and Zureick-Brown (RZB) label: X441
Rouse, Sutherland, and Zureick-Brown (RSZB) label: 16.64.2.1

Level structure

$\GL_2(\Z/16\Z)$-generators: $\begin{bmatrix}4&5\\1&12\end{bmatrix}$, $\begin{bmatrix}5&1\\15&4\end{bmatrix}$, $\begin{bmatrix}5&2\\14&3\end{bmatrix}$
$\GL_2(\Z/16\Z)$-subgroup: $(C_2\times C_8).D_{12}$
Contains $-I$: yes
Quadratic refinements: none in database
Cyclic 16-isogeny field degree: $24$
Cyclic 16-torsion field degree: $192$
Full 16-torsion field degree: $384$

Jacobian

Conductor: $2^{16}$
Simple: no
Squarefree: yes
Decomposition: $1^{2}$
Newforms: 256.2.a.a, 256.2.a.b

Models

Embedded model Embedded model in $\mathbb{P}^{4}$

$ 0 $ $=$ $ x^{2} - x w - y^{2} + y w - y t $
$=$ $x w + x t + y^{2} + y z$
$=$ $x y + x z + y t - z w - w^{2} + t^{2}$
$=$ $x y + x z + x w - x t + y z - y t - z^{2} + z w + t^{2}$
Copy content Toggle raw display

Singular plane model Singular plane model

$ 0 $ $=$ $ x^{6} + 2 x^{5} y + 2 x^{5} z + x^{4} y^{2} - 2 x^{4} y z - x^{4} z^{2} - 4 x^{3} y^{2} z - 4 x^{3} y z^{2} + \cdots + 3 z^{6} $
Copy content Toggle raw display

Weierstrass model Weierstrass model

$ y^{2} $ $=$ $ x^{6} - 3x^{4} + x^{2} + 1 $
Copy content Toggle raw display

Rational points

This modular curve has 7 rational CM points but no rational cusps or other known rational points. The following are the known rational points on this modular curve (one row per $j$-invariant).

Elliptic curve CM $j$-invariant $j$-heightPlane modelWeierstrass modelEmbedded model
27.a3 $-3$$0$ $0.000$$(-1/3:4/3:1)$, $(1:0:1)$$(-1/3:-28/27:1)$, $(1:0:1)$$(-1/4:3/4:0:5/4:1)$, $(-1:-1:0:1:0)$
121.b1 $-11$$-32768$ $= -1 \cdot 2^{15}$$10.397$$(0:-1:1)$$(0:1:1)$$(0:-1:1:0:1)$
361.a1 $-19$$-884736$ $= -1 \cdot 2^{15} \cdot 3^{3}$$13.693$$(-1:1:0)$$(1:-1:0)$$(-1:0:1:-1:1)$
27.a1 $-27$$-12288000$ $= -1 \cdot 2^{15} \cdot 3 \cdot 5^{3}$$16.324$$(-1:1:0)$$(1:1:0)$$(-1:0:-3:-1:1)$
1849.b1 $-43$$-884736000$ $= -1 \cdot 2^{18} \cdot 3^{3} \cdot 5^{3}$$20.601$$(-1:2:1)$$(-1:0:1)$$(-1/2:1/2:1:1/2:1)$
4489.b1 $-67$$-147197952000$ $= -1 \cdot 2^{15} \cdot 3^{3} \cdot 5^{3} \cdot 11^{3}$$25.715$$(0:3:1)$$(0:-1:1)$$(0:1/3:-1/3:4/3:1)$
26569.a1 $-163$$-262537412640768000$ $= -1 \cdot 2^{18} \cdot 3^{3} \cdot 5^{3} \cdot 23^{3} \cdot 29^{3}$$40.109$$(1/3:-22/3:1)$$(1/3:-28/27:1)$$(-1/22:-3/22:-7/11:29/22:1)$

Maps between models of this curve

Birational map from embedded model to plane model:

$\displaystyle X$ $=$ $\displaystyle x$
$\displaystyle Y$ $=$ $\displaystyle t$
$\displaystyle Z$ $=$ $\displaystyle y$

Birational map from embedded model to Weierstrass model:

$\displaystyle X$ $=$ $\displaystyle -x^{2}y+xy^{2}$
$\displaystyle Y$ $=$ $\displaystyle \frac{1}{2}x^{7}y^{2}-\frac{3}{2}x^{6}y^{3}+\frac{1}{2}x^{6}y^{2}t+\frac{1}{2}x^{5}y^{4}-3x^{5}y^{3}t+\frac{1}{2}x^{4}y^{5}+\frac{11}{2}x^{4}y^{4}t+\frac{5}{2}x^{3}y^{6}-2x^{3}y^{5}t-\frac{7}{2}x^{2}y^{7}-\frac{7}{2}x^{2}y^{6}t+\frac{1}{2}xy^{8}+3xy^{7}t+\frac{1}{2}y^{9}-\frac{1}{2}y^{8}t$
$\displaystyle Z$ $=$ $\displaystyle -xy^{2}+y^{3}$

Maps to other modular curves

$j$-invariant map of degree 64 from the embedded model of this modular curve to the modular curve $X(1)$ :

$\displaystyle j$ $=$ $\displaystyle 2^9\,\frac{462964514908356xzw^{9}-159622701463004xzw^{8}t-5586499641674960xzw^{7}t^{2}+98339629117519456xzw^{6}t^{3}+660043721859991996xzw^{5}t^{4}+1811818440155005436xzw^{4}t^{5}+2689283905141493832xzw^{3}t^{6}+2169235037419238336xzw^{2}t^{7}+801676094639586933xzwt^{8}+105703773285285725xzt^{9}+764218391014080xw^{10}-1422681489247728xw^{9}t-22522373083574348xw^{8}t^{2}-44221434561617504xw^{7}t^{3}-123507956973093864xw^{6}t^{4}-98944459836447792xw^{5}t^{5}+1297021708803009972xw^{4}t^{6}+3429877626231618864xw^{3}t^{7}+3026222413345985912xw^{2}t^{8}+1105715128834045788xwt^{9}+145001242570506361xt^{10}-344194600999320yw^{10}-613760207953940yw^{9}t+7242416301639188yw^{8}t^{2}+68757669266583168yw^{7}t^{3}+454192207729161240yw^{6}t^{4}+2153115125106462916yw^{5}t^{5}+5521753870957545992yw^{4}t^{6}+7407424001622272512yw^{3}t^{7}+4996199981368079954yw^{2}t^{8}+1580577721310723763ywt^{9}+187394150205078105yt^{10}-878903590461444z^{2}w^{9}-1364411485406936z^{2}w^{8}t+27019692189322672z^{2}w^{7}t^{2}+119136400325639152z^{2}w^{6}t^{3}+498793241211775140z^{2}w^{5}t^{4}+1588895244425821752z^{2}w^{4}t^{5}+2539942294658998408z^{2}w^{3}t^{6}+1869829879661457656z^{2}w^{2}t^{7}+625997847437722899z^{2}wt^{8}+78430539594860914z^{2}t^{9}+882988304923116zw^{10}-797279321277588zw^{9}t-42410312352477976zw^{8}t^{2}-300209294476449984zw^{7}t^{3}-1633225301148501820zw^{6}t^{4}-4912177167195051612zw^{5}t^{5}-7370480269298186708zw^{4}t^{6}-5256849485178408192zw^{3}t^{7}-1578479156802777953zw^{2}t^{8}-99541906717049253zwt^{9}+21478018504394454zt^{10}+420023790014760w^{11}-222007827036788w^{10}t-17171350383279944w^{9}t^{2}-133677282136718828w^{8}t^{3}-804116403857131040w^{7}t^{4}-2622863819236666348w^{6}t^{5}-4175163790899632788w^{5}t^{6}-2809214562478593836w^{4}t^{7}+153164347249758578w^{3}t^{8}+1289628483371624851w^{2}t^{9}+616156135862255766wt^{10}+88556445841800849t^{11}}{160884421854104xzw^{9}+783907179493848xzw^{8}t+7113484196409824xzw^{7}t^{2}+73883443751265056xzw^{6}t^{3}+216253400619214264xzw^{5}t^{4}+513000719280289880xzw^{4}t^{5}+706410178827880560xzw^{3}t^{6}+605995454487672176xzw^{2}t^{7}+290707789582317950xzwt^{8}+58728442699165534xzt^{9}+204716940975016xw^{10}-1041055751788112xw^{9}t-11426620397438432xw^{8}t^{2}-834702714687872xw^{7}t^{3}-72826404598991624xw^{6}t^{4}+125715601244581136xw^{5}t^{5}+431597447303421984xw^{4}t^{6}+821168694343805824xw^{3}t^{7}+803533110384664762xw^{2}t^{8}+405117041183791532xwt^{9}+82944839343229000xt^{10}-99991972555104yw^{10}+52873302391392yw^{9}t+7088960811070772yw^{8}t^{2}+48511681951020768yw^{7}t^{3}+239150957404891664yw^{6}t^{4}+786126101344212080yw^{5}t^{5}+1501610847412189852yw^{4}t^{6}+1888211366852569488yw^{3}t^{7}+1444119582782531728yw^{2}t^{8}+610453274493289792ywt^{9}+106760108225869589yt^{10}-236706127885096z^{2}w^{9}+419472055385488z^{2}w^{8}t+17352685251387808z^{2}w^{7}t^{2}+43497559973750912z^{2}w^{6}t^{3}+233919791207155608z^{2}w^{5}t^{4}+452741967960254512z^{2}w^{4}t^{5}+628676960764944784z^{2}w^{3}t^{6}+520282000819868128z^{2}w^{2}t^{7}+236336555547357662z^{2}wt^{8}+45070283085829636z^{2}t^{9}+190496912111224zw^{10}-2707457285415248zw^{9}t-36990893595416436zw^{8}t^{2}-163100094733990432zw^{7}t^{3}-668512011387826456zw^{6}t^{4}-1357401678464776736zw^{5}t^{5}-1850334192637822364zw^{4}t^{6}-1487566431828487024zw^{3}t^{7}-631922841934763314zw^{2}t^{8}-88224157576129772zwt^{9}+12239936199955595zt^{10}+98750129641384w^{11}-1076167028341984w^{10}t-16508299563052188w^{9}t^{2}-78780150573471152w^{8}t^{3}-342527329534286616w^{7}t^{4}-732986074388433808w^{6}t^{5}-1028158317114886900w^{5}t^{6}-747414337984133392w^{4}t^{7}-96574694801025694w^{3}t^{8}+287309177444371440w^{2}t^{9}+214139649237713681wt^{10}+49433156850459700t^{11}}$

Modular covers

Sorry, your browser does not support the nearby lattice.

Cover information

Click on a modular curve in the diagram to see information about it.

This modular curve minimally covers the modular curves listed below.

Covered curve Level Index Degree Genus Rank Kernel decomposition
$X_{\mathrm{ns}}^+(8)$ $8$ $4$ $4$ $0$ $0$ full Jacobian

This modular curve is minimally covered by the modular curves in the database listed below.

Covering curve Level Index Degree Genus Rank Kernel decomposition
$X_{\mathrm{ns}}(16)$ $16$ $2$ $2$ $7$ $2$ $1^{3}\cdot2$
16.128.7.b.1 $16$ $2$ $2$ $7$ $3$ $1^{3}\cdot2$
16.128.7.c.1 $16$ $2$ $2$ $7$ $3$ $1^{3}\cdot2$
16.128.7.d.1 $16$ $2$ $2$ $7$ $4$ $1^{3}\cdot2$
16.192.9.fv.2 $16$ $3$ $3$ $9$ $4$ $1^{5}\cdot2$
$X_{\mathrm{ns}}^+(32)$ $32$ $4$ $4$ $14$ $14$ $2^{2}\cdot4^{2}$
48.128.7.a.1 $48$ $2$ $2$ $7$ $7$ $1^{3}\cdot2$
48.128.7.b.1 $48$ $2$ $2$ $7$ $5$ $1^{3}\cdot2$
48.128.7.c.1 $48$ $2$ $2$ $7$ $6$ $1^{3}\cdot2$
48.128.7.d.1 $48$ $2$ $2$ $7$ $4$ $1^{3}\cdot2$
48.192.9.bro.1 $48$ $3$ $3$ $9$ $9$ $1^{3}\cdot2^{2}$
48.256.18.a.1 $48$ $4$ $4$ $18$ $9$ $1^{10}\cdot2^{3}$
80.128.7.a.1 $80$ $2$ $2$ $7$ $?$ not computed
80.128.7.b.1 $80$ $2$ $2$ $7$ $?$ not computed
80.128.7.c.1 $80$ $2$ $2$ $7$ $?$ not computed
80.128.7.d.1 $80$ $2$ $2$ $7$ $?$ not computed
80.320.23.a.1 $80$ $5$ $5$ $23$ $?$ not computed
112.128.7.e.1 $112$ $2$ $2$ $7$ $?$ not computed
112.128.7.f.1 $112$ $2$ $2$ $7$ $?$ not computed
112.128.7.g.1 $112$ $2$ $2$ $7$ $?$ not computed
112.128.7.h.1 $112$ $2$ $2$ $7$ $?$ not computed
176.128.7.a.1 $176$ $2$ $2$ $7$ $?$ not computed
176.128.7.b.1 $176$ $2$ $2$ $7$ $?$ not computed
176.128.7.c.1 $176$ $2$ $2$ $7$ $?$ not computed
176.128.7.d.1 $176$ $2$ $2$ $7$ $?$ not computed
208.128.7.a.1 $208$ $2$ $2$ $7$ $?$ not computed
208.128.7.b.1 $208$ $2$ $2$ $7$ $?$ not computed
208.128.7.c.1 $208$ $2$ $2$ $7$ $?$ not computed
208.128.7.d.1 $208$ $2$ $2$ $7$ $?$ not computed
240.128.7.a.1 $240$ $2$ $2$ $7$ $?$ not computed
240.128.7.b.1 $240$ $2$ $2$ $7$ $?$ not computed
240.128.7.c.1 $240$ $2$ $2$ $7$ $?$ not computed
240.128.7.d.1 $240$ $2$ $2$ $7$ $?$ not computed
272.128.7.a.1 $272$ $2$ $2$ $7$ $?$ not computed
272.128.7.b.1 $272$ $2$ $2$ $7$ $?$ not computed
272.128.7.c.1 $272$ $2$ $2$ $7$ $?$ not computed
272.128.7.d.1 $272$ $2$ $2$ $7$ $?$ not computed
304.128.7.a.1 $304$ $2$ $2$ $7$ $?$ not computed
304.128.7.b.1 $304$ $2$ $2$ $7$ $?$ not computed
304.128.7.c.1 $304$ $2$ $2$ $7$ $?$ not computed
304.128.7.d.1 $304$ $2$ $2$ $7$ $?$ not computed