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%I #13 Feb 08 2020 20:42:53
%S 1,3,5,7,11,13,17,29,37,41,43,67,95,97,109,113,115,119,167,179,181,
%T 205,211,215,229,235,265,281,319,359,373,401,413,421,439,443,461,505,
%U 545,559,719,745,775,941
%N The record values of d for the n in A239390.
%t greatestK[n_] := Module[{k = 1}, While[! PrimeQ[n^2 + (n - k)^2], k++]; k]; nn = 10000; t = {}; kMax = 0; Do[k = greatestK[n]; If[k > kMax, kMax = k; AppendTo[t, {n, k}]], {n, 2, nn}]; Transpose[t][[2]]
%Y Cf. A069002 (least number d such that n^2 + (n-d)^2 is prime).
%K nonn,more
%O 1,2
%A _T. D. Noe_, Mar 19 2014
%E a(38)-a(41) from _Chai Wah Wu_, Feb 06 2020
%E a(42)-a(44) from _Chai Wah Wu_, Feb 08 2020