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A275018 a(n) = A278846(n)/8.

%I A275018 #39 Jun 11 2024 15:45:17
%S A275018 0,0,0,0,0,1,1,5,6,10,11,19,20,29,33,38,43,56,60,76,81,90,98,118,121,
%T A275018 138,147,163,172,197,202,230,243,260,273,294,303,336,352,373,384,421,
%U A275018 430,470,487,508,528,572,583,623,640
%N A275018 a(n) = A278846(n)/8.
%H A275018 Indranil Ghosh and Chai Wah Wu, <a href="/A275018/b275018.txt">Table of n, a(n) for n = 0..10000</a> (terms n = 0..200 from Indranil Ghosh)
%o A275018 (Python)
%o A275018 def a(n):
%o A275018     s=0
%o A275018     for a in range(0, n+1):
%o A275018         for b in range(0, n+1):
%o A275018             for c in range(0, n+1):
%o A275018                 for d in range(0, n+1):
%o A275018                     if (a!=b  and a!=d and b!=d and c!=a and c!=b and c!=d):
%o A275018                         if abs(a*d-b*c)==1:
%o A275018                             s+=1
%o A275018     return s
%o A275018 print([int(a(n)/8) for n in range(0, 52)]) # _Indranil Ghosh_, Nov 30 2016
%Y A275018 Cf. A278846.
%K A275018 nonn
%O A275018 0,8
%A A275018 _Indranil Ghosh_, Nov 30 2016