In mathematical knot theory, 7<sub>4</sub> is the name of a 7-crossing knot which can be visually depicted in a highly-symmetric form, and so appears in the symbolism and/or artistic ornamentation of various cultures.
The interlaced version of the simplest form of the Endless knot symbol of Buddhism is topologically equivalent to the 7<sub>4</sub> knot (though it appears to have nine crossings), as is the interlaced version of the unicursal hexagram of occultism. (However, the endless knot symbol has more complex forms not equivalent to 7<sub>4</sub>, and both the endless knot and unicursal hexagram can appear in non-interlaced versions, in which case they are not knots at all.)
The 7<sub>4</sub> knot is a Lissajous knot, representable for example by the parametric equation