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A286479 a(n) = A046523(n+A000005(n)). 3

%I

%S 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,

%T 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,

%U 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

%N a(n) = A046523(n+A000005(n)).

%H Antti Karttunen, <a href="/A286479/b286479.txt">Table of n, a(n) for n = 1..10000</a>

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

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

%o (PARI)

%o 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

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

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

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

%o (Python)

%o from sympy import factorint, divisor_count

%o def P(n):

%o f = factorint(n)

%o return sorted([f[i] for i in f])

%o def a046523(n):

%o x=1

%o while True:

%o if P(n) == P(x): return x

%o else: x+=1

%o def a(n): return a046523(n + divisor_count(n)) # _Indranil Ghosh_, May 21 2017

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

%K nonn

%O 1,1

%A _Antti Karttunen_, May 21 2017

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Last modified August 13 06:22 EDT 2020. Contains 336442 sequences. (Running on oeis4.)