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A264987 Odd bisection of A263272. 4
1, 3, 5, 11, 9, 7, 13, 15, 23, 29, 33, 17, 35, 27, 19, 37, 21, 25, 31, 39, 41, 95, 45, 59, 113, 69, 77, 83, 87, 47, 101, 99, 65, 119, 51, 71, 89, 105, 53, 107, 81, 55, 109, 57, 73, 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 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..72.

FORMULA

a(n) = A263272((2*n)+1).

PROG

(Scheme) (define (A264987 n) (A263272 (+ 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*(2*n + 1))/2 # Indranil Ghosh, May 23 2017

CROSSREFS

Cf. A263272, A264986, A264989.

Sequence in context: A271314 A292006 A105603 * A170835 A122133 A273377

Adjacent sequences:  A264984 A264985 A264986 * A264988 A264989 A264990

KEYWORD

nonn

AUTHOR

Antti Karttunen, Dec 05 2015

STATUS

approved

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Last modified February 16 15:55 EST 2020. Contains 331961 sequences. (Running on oeis4.)