A130527 A permutation of the integers induced by the Beatty sequence for sqrt(2).

0, 1, 2, -1, 3, 4, -2, 5, 6, 7, -3, 8, 9, -4, 10, 11, 12, -5, 13, 14, -6, 15, 16, -7, 17, 18, 19, -8, 20, 21, -9, 22, 23, 24, -10, 25, 26, -11, 27, 28, -12, 29, 30, 31, -13, 32, 33, -14, 34, 35, 36, -15, 37, 38, -16, 39, 40, 41, -17, 42, 43, -18, 44, 45, -19, 46, 47, 48

Offset

0,3

Comments

Another permutation of the integers is -A130527.

Links

Table of n, a(n) for n=0..67.

Formula

a(0)=0; a(n)=k if n=L(k); a(n)=-k if n=U(k), where L(k) = A001951(k) = Floor(k*sqrt(2)), U(k) = A001952(k) = 2k+L(k).

Example

5=L(4), so a(5)=4.
6=U(2), so a(6)=-2.

Crossrefs

Cf. A001951, A001952, A130526.

Sequence in context: A009947 A166711 A026249 * A026366 A209125 A209137

Adjacent sequences: A130524 A130525 A130526 * A130528 A130529 A130530

Keyword

sign

Author

Clark Kimberling, Jun 02 2007

Status

approved