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%I #14 Oct 19 2017 03:14:29
%S 2,18,4,70,6,32,182,29718,1068,500,5604,10,8890182,776,1744,113582,
%T 4832118,1118,1111225770,1764132,14,1710,23156,71011068,16,82,
%U 8920484118,1063532,2482,126862368,352618
%N Let p(n) be the n-th prime congruent to 1 mod 4. Then a(n) = the least m for which m^2+1=p(n)*k^2 has a solution.
%C Subsequence of A191860. [_Reinhard Zumkeller_, Jun 18 2011]
%t f[n_] := Block[{y = 1}, While[ !IntegerQ[ Sqrt[n*y^2 - 1]], y++ ]; Sqrt[n*y^2 - 1]]; lst = {}; Do[p = Prime@ n; If[ Mod[p, 4] == 1, AppendTo[lst, f@p]; Print[{n, Prime@n, f@p}]], {n, 66}]; lst
%o (Haskell)
%o a094048 n = head [m | m <- map (a037213 . subtract 1 . (* a002144 n))
%o (tail a000290_list), m > 0]
%o -- _Reinhard Zumkeller_, Jun 13 2015
%Y Cf. A002144, A094049 (associated k), A130226, A137351, A179073.
%Y Cf. A000196, A037213, A000290.
%K nonn
%O 1,1
%A _Matthijs Coster_, Apr 29 2004
%E Edited by _Don Reble_, Apr 30 2004
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