3.14159265358979323846264338327950288419716939937510582097494459230781640628...
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, 13, 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