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A264983 Odd bisection of A263273.

%I A264983 #10 May 22 2017 20:07:36
%S A264983 1,3,7,5,9,19,13,21,25,11,15,23,17,27,55,37,57,73,31,39,67,49,63,61,
%T A264983 43,75,79,29,33,65,47,45,59,41,69,77,35,51,71,53,81,163,109,165,217,
%U A264983 91,111,199,145,171,181,127,219,235,85,93,193,139,117,175,121,201,229,103,147,211
%N A264983 Odd bisection of A263273.
%H A264983 Indranil Ghosh, <a href="/A264983/b264983.txt">Table of n, a(n) for n = 0..10000</a>
%F A264983 a(n) = A263273(2n + 1).
%t A264983 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 = Select[f /@ Range@ 130, OddQ] (* _Michael De Vlieger_, Jan 04 2016, after _Jean-François Alcover_ at A263273 *)
%o A264983 (Scheme) (define (A264983 n) (A263273 (+ 1 n n)))
%o A264983 (Python)
%o A264983 from sympy import factorint
%o A264983 from sympy.ntheory.factor_ import digits
%o A264983 from operator import mul
%o A264983 def a030102(n): return 0 if n==0 else int(''.join(map(str, digits(n, 3)[1:][::-1])), 3)
%o A264983 def a038502(n):
%o A264983     f=factorint(n)
%o A264983     return 1 if n==1 else reduce(mul, [1 if i==3 else i**f[i] for i in f])
%o A264983 def a038500(n): return n/a038502(n)
%o A264983 def a263273(n): return 0 if n==0 else a030102(a038502(n))*a038500(n)
%o A264983 def a(n): return a263273(2*n + 1) # _Indranil Ghosh_, May 22 2017
%Y A264983 Cf. A263273, A264984, A264985.
%K A264983 nonn,base
%O A264983 0,2
%A A264983 _Antti Karttunen_, Dec 05 2015