A265354 - OEIS

%I #9 May 22 2017 20:08:03

%S 0,1,3,2,4,9,6,10,12,7,5,19,8,13,27,18,28,36,21,11,57,24,37,30,15,31,

%T 39,22,16,64,23,14,55,20,46,58,25,17,73,26,40,81,54,82,108,63,29,171,

%U 72,109,90,45,85,117,66,34,192,69,38,165,60,100,174,75,35,219,78,118,84,33,91,93,48,32,138,51,112,111,42,94,120,67

%N Permutation of nonnegative integers: a(n) = A263273(A264985(n)).

%C Composition of A263273 with the permutation obtained from its odd bisection.

%H Antti Karttunen, <a href="/A265354/b265354.txt">Table of n, a(n) for n = 0..9841</a>

%H <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>

%F a(n) = A263273(A264985(n)).

%o (Scheme) (define (A265354 n) (A263273 (A264985 n)))

%o (Python)

%o from sympy import factorint

%o from sympy.ntheory.factor_ import digits

%o from operator import mul

%o def a030102(n): return 0 if n==0 else int(''.join(map(str, digits(n, 3)[1:][::-1])), 3)

%o def a038502(n):

%o     f=factorint(n)

%o     return 1 if n==1 else reduce(mul, [1 if i==3 else i**f[i] for i in f])

%o def a038500(n): return n/a038502(n)

%o def a263273(n): return 0 if n==0 else a030102(a038502(n))*a038500(n)

%o def a264985(n): return (a263273(2*n + 1) - 1)/2

%o def a(n): return a263273(a264985(n)) # _Indranil Ghosh_, May 22 2017

%Y Inverse: A265353.

%Y Cf. A263273, A264985.

%Y Cf. also A265352, A265355, A265356.

%K nonn,base

%O 0,3

%A _Antti Karttunen_, Dec 07 2015