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A372498 Complement of A372477.

%I A372498 #43 Jun 22 2024 18:19:29
%S A372498 8,11,14,15,18,22,23,29,32,35,38,40,41,45,47,51,53,54,55,58,59,62,66,
%T A372498 68,69,71,74,77,78,80,83,87,88,92,95,96,98,99,105,106,107,113,115,116,
%U A372498 118,119,123,125,126,128,130,131,134,135,137,138,141,143,149,150,153,154,155
%N A372498 Complement of A372477.
%C A372498 Sequence is complement of A372477.
%C A372498 This sequence consists of the positive integers that cannot be represented in the form (n*n + k*k - k*n, n*n + k*k - k*n + k - n), n > 0, 0 <= k < n.
%H A372498 Yury Kazakov, <a href="/A372498/b372498.txt">Table of n, a(n) for n = 1..1000</a>
%H A372498 N. A. Shikhova, <a href="https://vk.com/wall-125266332_63183">Discussion of a problem on the social network VK</a> (in Russian).
%H A372498 N. A. Shikhova, <a href="https://drive.google.com/file/d/1MfQnTIX7Aw-Y5ygTrUjRFryFuRna7OPf/view?usp=drive_link">Illustration for the sequence A372477</a>.
%o A372498 (Python)
%o A372498 import math
%o A372498 L=20 #tr are terms A372477 below L**2+1
%o A372498 numb=set()
%o A372498 Lmax=math.trunc((1+2*math.sqrt(3*L**2+1))/3)+1
%o A372498 tr=set()
%o A372498 tr.add(1)
%o A372498 for n in range(2,Lmax):
%o A372498   for k in range(0,n):
%o A372498     p1=n*n+k*k-k*n
%o A372498     p2=p1+k-n
%o A372498     if p1<=L**2:
%o A372498       tr.add(p1)
%o A372498     if p2<=L**2:
%o A372498       tr.add(p2)
%o A372498 for k in  range (1, L**2):
%o A372498   numb.add(k)
%o A372498 print(sorted(numb-tr))
%Y A372498 Complement of A372477.
%K A372498 nonn
%O A372498 1,1
%A A372498 _Yury Kazakov_, S. P. Obukhov, Sean Sun, and N. A. Shikhova, May 03 2024