A054427 Permutation of natural numbers: maps the fractions A038567/A038566 to the right side (n/m > 1) of Stern-Brocot tree.

1, 2, 4, 3, 8, 5, 16, 7, 6, 9, 32, 17, 64, 15, 13, 12, 10, 33, 128, 14, 11, 65, 256, 31, 25, 24, 18, 129, 512, 29, 20, 257, 1024, 63, 30, 28, 49, 48, 21, 19, 34, 513, 2048, 26, 23, 1025, 4096, 127, 61, 57, 27, 97, 96, 22, 40, 36, 66, 2049, 8192, 62, 56, 41, 35, 4097

Offset: 1

Author

Antti Karttunen

Keywords

• nonn

Examples

			Right side of Stern-Brocot tree: 1/1 2/1 3/2 3/1 4/3 5/3 5/2 4/1 5/4 7/5 8/5 7/4 7/3 8/3 7/2 5/1
A038567/A038566: 1/1 2/1 3/1 3/2 4/1 4/3 5/1 5/2 5/3 5/4 6/1 6/5 7/1 7/2 7/3 7/4
		

Links

• Index entries for sequences related to Stern's sequences
• Index entries for sequences that are permutations of the natural numbers

Crossrefs

A038567/A038566 = shift_left(A007306)/A047679(A054427(.)).

Inverse permutation: A054428.

Programs

Maple

A038567_A038566_to_SternBrocot_permutation := proc(u) local a,n,i; a := []; for n from 1 to u do for i from 1 to n do if (1 = igcd(n,i)) then a := [op(a),cfrac2binexp(convert((n/i),confrac))+1]; fi; od; od; RETURN(a); end; # cfrac2binexp given in A054424.