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A264986 Even bisection of A263272; terms of A264974 doubled. 4
0, 2, 4, 6, 8, 10, 12, 14, 32, 18, 20, 38, 24, 26, 28, 30, 16, 34, 36, 22, 40, 42, 68, 86, 96, 50, 104, 54, 56, 110, 60, 74, 92, 114, 44, 98, 72, 62, 116, 78, 80, 82, 84, 46, 100, 90, 64, 118, 48, 70, 88, 102, 52, 106, 108, 58, 112, 66, 76, 94, 120, 122, 284, 126, 176, 338, 204, 230, 248, 258, 140, 302, 288 (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).

a(n) = 2 * A264974(n).

a(n) = A263273(4*n)/2.

PROG

(Scheme) (define (A264986 n) (A263272 (+ 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(4*n)/2 # Indranil Ghosh, May 23 2017

CROSSREFS

Cf. A263272, A264974, A264987.

Sequence in context: A189562 A194372 A058218 * A140955 A111905 A255385

Adjacent sequences:  A264983 A264984 A264985 * A264987 A264988 A264989

KEYWORD

nonn

AUTHOR

Antti Karttunen, Dec 05 2015

STATUS

approved

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Last modified November 17 16:08 EST 2019. Contains 329241 sequences. (Running on oeis4.)