cp's OEIS Frontend

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.

A094049 Let p(n) be the n-th prime congruent to 1 mod 4. Then a(n) = the least k for which m^2+1=p(n)*k^2 has a solution.

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%I A094049 #7 Oct 19 2017 03:14:29
%S A094049 1,5,1,13,1,5,25,3805,125,53,569,1,851525,73,149,9305,385645,85,
%T A094049 82596761,126985,1,113,1517,4574225,1,5,535979945,63445,145,7170685,
%U A094049 19805,55335641,493,3793,265,65,1027776565,1
%N A094049 Let p(n) be the n-th prime congruent to 1 mod 4. Then a(n) = the least k for which m^2+1=p(n)*k^2 has a solution.
%t A094049  f[n_] := Block[{y = 1}, While[ !IntegerQ[ Sqrt[n*y^2 - 1]], y++]; y]; lst = {}; Do[p = Prime@n; If[Mod[p, 4] == 1, AppendTo[lst, f@p]; Print[{n, f@p}]], {n, 66}]; lst
%Y A094049 Cf. A002144, A094048.
%K A094049 nonn
%O A094049 1,2
%A A094049 _Matthijs Coster_, Apr 29 2004
%E A094049 Edited by _Don Reble_, Apr 30 2004