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.
%I A002199 M0245 N0085 #32 Dec 19 2024 05:33:24
%S A002199 1,1,2,2,3,2,3,4,2,2,7,2,6,9,2,2,3,2,4,2,5,2,3,3,5,2,2,3,6,3,9,3,3,4,
%T A002199 2,5,5,4,2,2,3,2,2,5,2,2,4,9,3,6,3,2,7,3,3,2,2,2,5,3,6,2,7,2,10,2,5,
%U A002199 10,3,2,3,2,2,2,4,2,2,5,3,21,3,2,5,5,5,3,3,13,2,2,3,2,2,4,5,2,2,3,4,2,4,2,3
%N A002199 Least negative primitive root of n-th prime.
%D A002199 M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 864.
%D A002199 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
%D A002199 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H A002199 T. D. Noe, <a href="/A002199/b002199.txt">Table of n, a(n) for n=1..10000</a>
%H A002199 M. Abramowitz and I. A. Stegun, eds., <a href="http://www.convertit.com/Go/ConvertIt/Reference/AMS55.ASP">Handbook of Mathematical Functions</a>, National Bureau of Standards, Applied Math. Series 55, Tenth Printing, 1972 [alternative scanned copy].
%H A002199 A. E. Western and J. C. P. Miller, <a href="/A002223/a002223.pdf">Tables of Indices and Primitive Roots</a>, Royal Society Mathematical Tables, Vol. 9, Cambridge Univ. Press, 1968 [Annotated scans of selected pages]
%F A002199 a(n) = prime(n) - A071894(n). - _T. D. Noe_, Oct 24 2005
%t A002199 Table[(k=-1;While[MultiplicativeOrder[k,p]!=p-1,k--];-k),{p,Prime@Range@100}] (* _Giorgos Kalogeropoulos_, Sep 28 2023 *)
%Y A002199 Cf. A060749, A001918.
%K A002199 nonn
%O A002199 1,3
%A A002199 _N. J. A. Sloane_