A285337 - OEIS

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A285337

a(n) = denominator of A065642(n)/n.

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 4, 1, 1, 1, 1, 3, 1, 1, 8, 1, 5, 1, 1, 1, 3, 1, 4, 1, 1, 1, 2, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 5, 1, 1, 1, 1, 4, 1, 1, 1, 2, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 8, 1, 7, 1, 5, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 4, 1, 1, 1, 1, 1, 1, 1, 4

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,12

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..10000

PROG

(Scheme) (define (A285337 n) (denominator (/ (A065642 n) n)))

(Python)

from sympy import primefactors, prod, Integer

def a007947(n): return 1 if n<2 else prod(primefactors(n))

def a065642(n):

if n==1: return 1

r=a007947(n)

n += r

while a007947(n)!=r:

n+=r

return n

def a(n): return (a065642(n)/Integer(n)).denominator() # Indranil Ghosh, Apr 20 2017

CROSSREFS

Cf. A065642, A285100 (positions of ones), A284342 (positions of terms > 1).

Cf. A285336 for the numerator.

Sequence in context: A319094 A069283 A319430 * A328457 A340827 A360119

Adjacent sequences: A285334 A285335 A285336 * A285338 A285339 A285340

KEYWORD

nonn,frac

AUTHOR

Antti Karttunen, Apr 19 2017

STATUS

approved