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A363762 Numbers k for which A363763(k) = -1.

%I A363762 #26 Jul 13 2023 07:26:50
%S A363762 46,55,62,71,80,86,107,130,172,187,195,208,222,247,259,263,268,272,
%T A363762 280,297,314,330,358,363,370,372,379,394,400,405,429,449,450,462,489,
%U A363762 500,529,534,587,629,641,646,652,667,668,672,704,715,733,736,749,769,775,776,778,785,793,799
%N A363762 Numbers k for which A363763(k) = -1.
%H A363762 Hugo Pfoertner, <a href="/A363762/b363762.txt">Table of n, a(n) for n = 1..2400</a>
%o A363762 (Python)
%o A363762 from itertools import count, islice
%o A363762 from sympy import factorint
%o A363762 def A363762_gen(startvalue=1): # generator of terms >= startvalue
%o A363762     for n in count(max(startvalue,1)):
%o A363762         for k in range(n>>1,((n+1)**2<<1)+1):
%o A363762             c = 0
%o A363762             for m in range(k**2+1,(k+1)**2):
%o A363762                 if all(p==2 or p&3==1 or e&1^1 for p, e in factorint(m).items()):
%o A363762                     c += 1
%o A363762                     if c>n:
%o A363762                         break
%o A363762             if c==n:
%o A363762                 break
%o A363762         else:
%o A363762             yield n
%o A363762 A363762_list = list(islice(A363762_gen(),20)) # _Chai Wah Wu_, Jun 22 2023
%Y A363762 Cf. A001481, A004018, A363522, A363761.
%Y A363762 Numbers not occurring as terms of A077773.
%K A363762 nonn
%O A363762 1,1
%A A363762 _Hugo Pfoertner_, Jun 20 2023