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A286363 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)).

%I A286363 #13 May 09 2017 14:24:51
%S A286363 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 A286363 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 A286363 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 A286363 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 A286363 Antti Karttunen, <a href="/A286363/b286363.txt">Table of n, a(n) for n = 1..10000</a>
%F A286363 a(n) = A046523(A097706(n)).
%F A286363 a(n) = A286361(A267099(n)).
%o A286363 (Scheme) (define (A286363 n) (A046523 (A097706 n)))
%o A286363 (Python)
%o A286363 from sympy import factorint
%o A286363 from operator import mul
%o A286363 def P(n):
%o A286363     f = factorint(n)
%o A286363     return sorted([f[i] for i in f])
%o A286363 def a046523(n):
%o A286363     x=1
%o A286363     while True:
%o A286363         if P(n) == P(x): return x
%o A286363         else: x+=1
%o A286363 def a072436(n):
%o A286363     f = factorint(n)
%o A286363     return 1 if n == 1 else reduce(mul, [1 if i%4==3 else i**f[i] for i in f])
%o A286363 def a(n): return a046523(n/a072436(n)) # _Indranil Ghosh_, May 09 2017
%Y A286363 Cf. A046523, A097706, A286361, A286364, A286365.
%Y A286363 Cf. also A065338, A065339, A260728, A267099.
%K A286363 nonn
%O A286363 1,3
%A A286363 _Antti Karttunen_, May 08 2017