A131968 Interspersion of the Farey fractal sequence, A131967.

1, 3, 2, 6, 5, 4, 11, 10, 8, 7, 18, 17, 14, 13, 9, 29, 28, 23, 21, 15, 12, 42, 41, 35, 33, 25, 20, 16, 61, 60, 51, 48, 37, 32, 26, 19, 86, 85, 71, 68, 54, 46, 38, 31, 22

Offset

1,2

Comments

A permutation of the natural numbers.

References

C. Kimberling, "Fractal sequences and interspersions," Ars Combinatoria 45 (1997) 157-168.

Links

Table of n, a(n) for n=1..45.

Formula

Rectangular array T given by antidiagonals. T(i,j) = the j-th index n such that A131967(n)=i.

Example

Northwest corner:
1 3 6 11 18
2 5 10 17 28
4 8 14 23 35
7 13 21 33 48

Crossrefs

Cf. A131967.

Sequence in context: A145522 A283939 A293056 * A191740 A132665 A255122

Adjacent sequences: A131965 A131966 A131967 * A131969 A131970 A131971

Keyword

nonn,tabl

Author

Clark Kimberling, Aug 02 2007

Status

approved