A380141 Decimal expansion of the real part of (-1)^sqrt(i), negated, where i is the imaginary unit.

0, 6, 5, 6, 8, 9, 7, 6, 4, 7, 3, 5, 1, 5, 3, 5, 3, 2, 0, 9, 0, 2, 6, 6, 8, 7, 9, 9, 6, 7, 6, 6, 1, 0, 1, 0, 3, 3, 6, 5, 0, 8, 9, 1, 5, 3, 4, 7, 5, 0, 3, 9, 9, 9, 6, 8, 5, 7, 0, 0, 4, 6, 9, 9, 0, 6, 3, 7, 1, 3, 2, 9, 1, 5, 2, 3, 9, 9, 2, 2, 9, 0, 3, 5, 6, 0, 4, 6

Offset: 0

Author

Hugo Pfoertner, Jan 23 2025

Keywords

• nonn
• cons
• easy

Examples

			0.0656897647351535320902668799676610103365089153475...
		

Links

• Math Beast, Oxford university entrance exam question, YouTube video, 2025.

Crossrefs

A380142 is the imaginary part.

Cf. A247719.

Programs

Maple

evalf[140](-Re((-1)^sqrt(I)));  # Alois P. Heinz, Jan 23 2025

Mathematica

Prepend[RealDigits[Re[(-1)^Sqrt[I]], 10, 87][[1]], 0] (* Shenghui Yang, Jan 23 2025 *)

PARI

real((-1)^sqrt(I))

Formula

Equals -cos(Pi/sqrt(2))/exp(Pi/sqrt(2)).