3.1415926535897932384626433832795028841971693993751058209749445923...

π is a transcendental number

[3; 7, 15, 1, 292, 1, 1, 1, 2, 1, 3, 1, 14, 2, 1, 1, 2, 2, 2, 2, 1, 84, 2, 1, 1, 15, 3, 1, ...]

π = 180 °

π = -i log(-1)

π = cos^(-1)(-1)

π = 4 sum_(k=0)^∞ (-1)^k/(2 k + 1)

π = -2 + 2 sum_(k=1)^∞ 2^k/binomial(2 k, k)

π = sum_(k=0)^∞ (50 k - 6)/(2^k binomial(3 k, k))

π = 2 integral_0^∞ 1/(t^2 + 1) dt

π = 4 integral_0^1 sqrt(1 - t^2)dt

π = 2 integral_0^∞ sin(t)/t dt