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A286479 a(n) = A046523(n+A000005(n)). 3
2, 4, 2, 2, 2, 6, 4, 12, 12, 6, 2, 12, 6, 12, 2, 6, 2, 24, 6, 6, 4, 6, 4, 32, 12, 30, 2, 6, 2, 6, 6, 6, 2, 6, 6, 12, 6, 30, 2, 48, 2, 12, 12, 12, 6, 12, 4, 6, 12, 24, 6, 6, 6, 6, 2, 64, 2, 6, 2, 72, 12, 30, 6, 2, 6, 6, 6, 6, 2, 30, 2, 60, 12, 30, 16, 6, 16, 6, 16, 60, 6, 6, 6, 96, 2, 60, 6, 96, 6, 30, 6, 12, 2, 12, 12, 72, 12, 24, 30, 2, 2, 30, 30, 48, 2, 30 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

a(n) = A046523(A062249(n)) = A046523(n+A000005(n)).

MATHEMATICA

Table[Times @@ MapIndexed[Prime[First[#2]]^#1 &, Sort[FactorInteger[n + DivisorSigma[0, n]][[All, -1]], Greater]], {n, 106}] (* Michael De Vlieger, May 21 2017 *)

PROG

(PARI)

A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); };  \\ This function from Charles R Greathouse IV, Aug 17 2011

A286479(n) = A046523(n+numdiv(n));

for(n=1, 10000, write("b286479.txt", n, " ", A286479(n)));

(Scheme) (define (A286479 n) (A046523 (+ n (A000005 n))))

(Python)

from sympy import factorint, divisor_count

def P(n):

    f = factorint(n)

    return sorted([f[i] for i in f])

def a046523(n):

    x=1

    while True:

        if P(n) == P(x): return x

        else: x+=1

def a(n): return a046523(n + divisor_count(n)) # Indranil Ghosh, May 21 2017

CROSSREFS

Cf. A000005, A046523, A062249, A286480, A286529.

Sequence in context: A072865 A322728 A179686 * A013604 A218217 A218279

Adjacent sequences:  A286476 A286477 A286478 * A286480 A286481 A286482

KEYWORD

nonn

AUTHOR

Antti Karttunen, May 21 2017

STATUS

approved

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Last modified August 20 20:50 EDT 2019. Contains 326155 sequences. (Running on oeis4.)