A265904 Self-inverse permutation of nonnegative integers: a(n) = A263272(A263273(A263272(n))).

0, 1, 2, 3, 4, 11, 6, 29, 8, 9, 10, 5, 12, 13, 38, 33, 92, 17, 18, 83, 20, 87, 110, 35, 24, 89, 26, 27, 28, 7, 30, 37, 32, 15, 86, 23, 36, 31, 14, 39, 40, 119, 114, 281, 44, 99, 254, 65, 276, 335, 98, 51, 260, 71, 54, 245, 56, 249, 326, 101, 60, 263, 74, 261, 272, 47, 330, 353, 116, 105, 278, 53, 72, 251, 62, 267, 332, 107, 78, 269, 80, 81, 82, 19

Offset: 0

Author

Antti Karttunen, Jan 02 2016

Keywords

• nonn
• base

Comments

A263273 conjugated with the permutation obtained from its even bisection.

Links

• Antti Karttunen, Table of n, a(n) for n = 0..6561
• Index entries for sequences that are permutations of the natural numbers

Crossrefs

Cf. A000035, A263272, A263273, A265351, A265352.

Cf. also A265902.

Cf. A265369, A266190, A266401, A266403 (other conjugates or similar derivations of A263273).

Programs

Mathematica

f[n_] := Block[{g, h}, g[x_] := x/3^IntegerExponent[x, 3]; h[x_] := x/g@ x; If[n == 0, 0, FromDigits[Reverse@ IntegerDigits[#, 3], 3] &@g[n] h[n]]]; t = Table[f[2 n]/2, {n, 0, 1000}]; Table[t[[f[t[[n + 1]]] + 1]], {n, 0, 83}] (* Michael De Vlieger, Jan 04 2016, after Jean-François Alcover at A263273 *)

Python

from sympy import factorint
from sympy.ntheory.factor_ import digits
from operator import mul
def a030102(n): return 0 if n==0 else int(''.join(map(str, digits(n, 3)[1:][::-1])), 3)
def a038502(n):
    f=factorint(n)
    return 1 if n==1 else reduce(mul, [1 if i==3 else i**f[i] for i in f])
def a038500(n): return n/a038502(n)
def a263273(n): return 0 if n==0 else a030102(a038502(n))*a038500(n)
def a263272(n): return a263273(2*n)/2
def a(n): return a263272(a263273(a263272(n))) # Indranil Ghosh, May 25 2017

Scheme

(define (A265904 n) (A263272 (A263273 (A263272 n))))

Formula

a(n) = A263272(A263273(A263272(n))).

As a composition of related permutations:

a(n) = A263272(A265352(n)).

a(n) = A265351(A263272(n)).

Other identities. For all n >= 0:

a(3*n) = 3*a(n).

A000035(a(n)) = A000035(n). [This permutation preserves the parity of n.]