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Values of k associated with A060397.
5

%I #13 Aug 15 2022 08:34:41

%S 1,0,0,1,0,0,1,0,0,1,0,1,1,0,2,1,0,0,1,0,0,1,0,1,1,0,1,1,0,2,1,0,0,1,

%T 0,2,1,0,0,1,0,1,1,0,2,1,0,0,1,0,4,1,0,3,1,0,1,1,0,2,1,0,0,1,0,1,1,0,

%U 2,1,0,1,1,0,2,1,0,0,1,0,0,1,0,4,1,0,1,1,0,2,1,0,0,1,0,3,1,0,2,1,0,1,1,0,2

%N Values of k associated with A060397.

%H T. D. Noe, <a href="/A060398/b060398.txt">Table of n, a(n) for n = 0..10000</a>

%H Carlos Rivera, <a href="http://www.primepuzzles.net/conjectures/conj_017.htm">Conjecture 17. The Ludovicus conjecture about the Euler trinomials</a>, The Prime Puzzles & Problems Connection.

%t a[n_] := Switch[n, 0, 1, _, Module[{f, kmax0 = 2}, f[kmax_] := f[kmax] = MinimalBy[Table[{k, FactorInteger[k^2 + k + 2 n + 1][[1, 1]]}, {k, 0, kmax}], Last, 1]; f[kmax = kmax0]; f[kmax = 2 kmax]; While[f[kmax] != f[kmax/2], kmax = 2 kmax]; f[kmax][[1, 1]]]];

%t Table[a[n], {n, 0, 105}] (* _Jean-François Alcover_, Aug 15 2022 *)

%Y Cf. A060397.

%K nonn,easy

%O 0,15

%A _N. J. A. Sloane_, Apr 04 2001

%E More terms from _T. D. Noe_, Mar 12 2007