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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A362935 a(n) = (A000982(n) - A132188(n))/2.

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%I A362935 #11 Aug 29 2023 10:12:04
%S A362935 0,0,1,1,3,5,8,10,12,16,21,25,31,37,44,48,56,62,71,79,89,99,110,120,
%T A362935 128,140,151,163,177,191,206,218,234,250,267,279,297,315,334,352,372,
%U A362935 392,413,433,453,475,498,518,536,556,581,605,631,655,682,708,736,764,793,821,851,881,910,934,966,998
%N A362935 a(n) = (A000982(n) - A132188(n))/2.
%C A362935 a(n) = one-half of (number of pairs (i,j) in [1..n] X [1..n] with integral arithmetic mean) - (number of pairs (i,j) in [1..n] X [1..n] with integral geometric mean).
%H A362935 Alois P. Heinz, <a href="/A362935/b362935.txt">Table of n, a(n) for n = 1..10000</a>
%F A362935 a(n) = A362934(n)/2.
%o A362935 (Python)
%o A362935 from sympy.ntheory.primetest import is_square
%o A362935 def A362935(n): return ((n-1)**2>>2)-sum(1 for x in range(1,n+1) for y in range(1,x) if is_square(x*y)) # _Chai Wah Wu_, Aug 29 2023
%Y A362935 Cf. A000982, A132188, A362931-A932937.
%K A362935 nonn
%O A362935 1,5
%A A362935 _N. J. A. Sloane_, Aug 28 2023