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A181763 a(n) = A061037(n)^2.

%I A181763 #24 Aug 03 2025 03:22:30
%S A181763 0,25,9,441,4,2025,225,5929,36,13689,1225,27225,144,48841,3969,81225,
%T A181763 400,127449,9801,190969,900,275625,20449,385641,1764,525625,38025,
%U A181763 700569,3136,915849,65025,1177225,5184,1490841,104329,1863225,8100
%N A181763 a(n) = A061037(n)^2.
%C A181763 A061038(n)/a(n+2) for n >= 2 gives the reduced fractions 1/9, 4/49, 4, 4/81, 1/25, 4/121, 16/9, 4/169, ...
%H A181763 G. C. Greubel, <a href="/A181763/b181763.txt">Table of n, a(n) for n = 2..1000</a>
%F A181763 Sum_{n>=3} 1/a(n) = 79*Pi^2/192 - 65/18. - _Amiram Eldar_, Aug 14 2022
%t A181763 A061037[n_] := Numerator[(n - 2)*(n + 2)/(4 n^2)]; Table[A061037[n]^2, {n, 2, 100}] (* _G. C. Greubel_, Sep 19 2018 *)
%o A181763 (Magma) A061037:=func< n | Numerator(1/4-1/n^2) >; A181763:=func< n | A061037(n)^2 >; [ A181763(n): n in [2..50] ]; // _Klaus Brockhaus_, Jan 09 2011
%o A181763 (PARI) a(n) = numerator((n-2)*(n+2)/(4*n^2))^2;
%o A181763 for(n=2, 50, print1(a(n), ", ")) \\ _G. C. Greubel_, Sep 19 2018
%Y A181763 Cf. A061037, A061038.
%K A181763 nonn,easy
%O A181763 2,2
%A A181763 _Paul Curtz_, Nov 14 2010