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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.

A059592 Square-full part of n^2 + 1.

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%I A059592 #19 Nov 12 2023 13:04:57
%S A059592 1,1,1,1,1,1,1,5,1,1,1,1,1,1,1,1,1,1,5,1,1,1,1,1,1,1,1,1,1,1,1,1,5,1,
%T A059592 1,1,1,1,17,1,1,29,1,5,1,1,1,1,1,1,1,1,1,1,1,1,1,5,1,1,1,1,1,1,1,1,1,
%U A059592 1,5,1,13,1,1,1,1,1,1,1,1,1,1,1,5,1,1,1,1,1,1,1,1,1,1,5,1,1,1,1,1,13,1,1,1
%N A059592 Square-full part of n^2 + 1.
%C A059592 Related to period-1 continued fractions [z,z,z,...].
%C A059592 A124808 gives number of numbers m <= n with a(m)=1. - _Reinhard Zumkeller_, Nov 08
%H A059592 Reinhard Zumkeller, <a href="/A059592/b059592.txt">Table of n, a(n) for n = 0..1000</a> (corrected by _Sean A. Irvine_)
%F A059592 a(n) = A000188(A002522(n)).
%F A059592 a(n)^2 * A059591(n) = n^2 + 1.
%e A059592 a(7)=5 since 7^2 + 1 = 50 = 25*2 = (5^2)*2.
%o A059592 (PARI) a(n) = core(n^2+1, 1)[2]; \\ _Michel Marcus_, Nov 12 2023
%Y A059592 Cf. A000188, A059591, A007913, A002522.
%K A059592 easy,nonn
%O A059592 0,8
%A A059592 _Marc LeBrun_, Jan 25 2001