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Least number with the same prime signature as {the largest divisor of n with only prime factors of the form 4k+3} has: a(n) = A046523(A097706(n)).
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%I #13 May 09 2017 14:24:51

%S 1,1,2,1,1,2,2,1,4,1,2,2,1,2,2,1,1,4,2,1,6,2,2,2,1,1,8,2,1,2,2,1,6,1,

%T 2,4,1,2,2,1,1,6,2,2,4,2,2,2,4,1,2,1,1,8,2,2,6,1,2,2,1,2,12,1,1,6,2,1,

%U 6,2,2,4,1,1,2,2,6,2,2,1,16,1,2,6,1,2,2,2,1,4,2,2,6,2,2,2,1,4,12,1,1,2,2,1,6,1,2,8,1,2,2,2,1,6,2,1,4,2,2,2

%N Least number with the same prime signature as {the largest divisor of n with only prime factors of the form 4k+3} has: a(n) = A046523(A097706(n)).

%H Antti Karttunen, <a href="/A286363/b286363.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A046523(A097706(n)).

%F a(n) = A286361(A267099(n)).

%o (Scheme) (define (A286363 n) (A046523 (A097706 n)))

%o (Python)

%o from sympy import factorint

%o from operator import mul

%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 a072436(n):

%o f = factorint(n)

%o return 1 if n == 1 else reduce(mul, [1 if i%4==3 else i**f[i] for i in f])

%o def a(n): return a046523(n/a072436(n)) # _Indranil Ghosh_, May 09 2017

%Y Cf. A046523, A097706, A286361, A286364, A286365.

%Y Cf. also A065338, A065339, A260728, A267099.

%K nonn

%O 1,3

%A _Antti Karttunen_, May 08 2017