cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A065659 The table of permutations of N, each row induced by the rotation (to the left) of the n-th node in the infinite binary "decimal" fraction tree.

Original entry on oeis.org

4, 16, 1, 22, 136, 1, 64, 3, 2, 1, 8, 64, 25, 2, 1, 160, 19, 4, 3, 76, 1, 1, 6, 5, 4, 3, 2, 1, 256, 7, 97, 5, 4, 3328, 2, 1, 32, 256, 13, 6, 167772160, 4, 3, 2, 1, 67, 1054, 8, 7, 6, 5, 4, 3, 2, 1, 34, 4, 9, 130, 7, 97, 5, 4, 3, 1249, 1, 1279, 40, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 10, 12
Offset: 0

Views

Author

Antti Karttunen, Nov 22 2001

Keywords

Comments

See the comment at A065658.

Crossrefs

The first row (rotate the top node left): A065661, 2nd row (rotate the top node's left child): A065663, 3rd row (rotate the top node's right child): A065665, 4th row: A065667, 5th row: A065669, 6th row: A065671, 7th row: A065673. Cf. also A065674-A065676. For the other needed Maple procedures follow A065658 which gives the inverse permutations.

Programs

  • Maple
    [seq(RotateBinFracLeftTable(j),j=0..119)]; RotateBinFracLeftTable := n -> RotateBinFracNodeLeft(1+(n-((trinv(n)*(trinv(n)-1))/2)),(((trinv(n)-1)*(((1/2)*trinv(n))+1))-n)+1);
    RotateBinFracNodeLeft := (t,n) -> frac2position_in_0_1_SB_tree(RotateBinFracNodeLeft_x(t,SternBrocot0_1frac(n)));
    RotateBinFracNodeLeft_x := proc(t,x) local num,den; den := 2^(1+floor_log_2(t)); num := (2*(t-(den/2)))+1; if((x <= (num-1)/den) or (x >= (num+1)/den)) then RETURN(x); fi; if(x >= ((2*num)+1)/(2*den)) then RETURN(((num-1)/den) + (2*(x - (num/den)))); fi; if(x > (num/den)) then RETURN(x - (1/(2*den))); fi; RETURN(((num-1)/den) + ((x-((num-1)/den))/2)); end;
    SternBrocot0_1frac := proc(n) local m; m := n + 2^floor_log_2(n); SternBrocotTreeNum(m)/SternBrocotTreeDen(m); end;
    frac2position_in_0_1_SB_tree := r -> RETURN(ReflectBinTreePermutation(cfrac2binexp(convert(1/r,confrac))));

A065670 Permutation of N induced by rotating the node 6 right in the infinite planar binary tree shown at A065658.

Original entry on oeis.org

1, 2, 115, 4, 5, 234881023, 7, 8, 9, 10, 11, 877, 112, 475, 15, 16, 17, 18, 19, 20, 21, 22, 23, 52, 445, 57355, 3616, 235, 1915, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 103, 13, 14191, 28615, 917506, 229630, 3613, 454, 934, 120832
Offset: 1

Views

Author

Antti Karttunen, Nov 22 2001

Keywords

Examples

			This permutation touches only the rationals in the range ]1/2, 3/4[, which for example contains the sixth node = 3/5 of the SB ]0,1[ tree (A007305/A007306) which has an infinite, but periodic binary fractional expansion 0.100110011001... and by this permutation it is changed to 0.1010100110011001... = 53/80, which is located as the 234881023th node in the SB ]0,1[ tree.
		

Crossrefs

The sixth row of A065658. Inverse of A065671.

Programs

  • Maple
    [seq(RotateBinFracNodeRight(6,j),j=1..256)];
Showing 1-2 of 2 results.