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%I #8 May 23 2017 20:59:38
%S 1,3,5,11,9,7,13,15,23,29,33,17,35,27,19,37,21,25,31,39,41,95,45,59,
%T 113,69,77,83,87,47,101,99,65,119,51,71,89,105,53,107,81,55,109,57,73,
%U 91,111,43,97,63,61,115,75,79,85,93,49,103,117,67,121,123,203,257,285,149,311,135,167,329,177,221,275
%N Odd bisection of A263272.
%F a(n) = A263272((2*n)+1).
%o (Scheme) (define (A264987 n) (A263272 (+ 1 n 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 a(n): return a263273(2*(2*n + 1))/2 # _Indranil Ghosh_, May 23 2017
%Y Cf. A263272, A264986, A264989.
%K nonn
%O 0,2
%A _Antti Karttunen_, Dec 05 2015
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