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A264983 Odd bisection of A263273. 4
1, 3, 7, 5, 9, 19, 13, 21, 25, 11, 15, 23, 17, 27, 55, 37, 57, 73, 31, 39, 67, 49, 63, 61, 43, 75, 79, 29, 33, 65, 47, 45, 59, 41, 69, 77, 35, 51, 71, 53, 81, 163, 109, 165, 217, 91, 111, 199, 145, 171, 181, 127, 219, 235, 85, 93, 193, 139, 117, 175, 121, 201, 229, 103, 147, 211 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Indranil Ghosh, Table of n, a(n) for n = 0..10000

FORMULA

a(n) = A263273(2n + 1).

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 = Select[f /@ Range@ 130, OddQ] (* Michael De Vlieger, Jan 04 2016, after Jean-Fran├žois Alcover at A263273 *)

PROG

(Scheme) (define (A264983 n) (A263273 (+ 1 n n)))

(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 a(n): return a263273(2*n + 1) # Indranil Ghosh, May 22 2017

CROSSREFS

Cf. A263273, A264984, A264985.

Sequence in context: A021270 A259565 A113910 * A265341 A094009 A088514

Adjacent sequences:  A264980 A264981 A264982 * A264984 A264985 A264986

KEYWORD

nonn,base

AUTHOR

Antti Karttunen, Dec 05 2015

STATUS

approved

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Last modified October 20 17:42 EDT 2019. Contains 328268 sequences. (Running on oeis4.)