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 A089105 #26 Jul 07 2023 09:33:45 %S A089105 2,3,5,6,7,10,11,12,13,14,15,17,18,19,20,21,22,23,24,26 %N A089105 Values taken by least witness function W(n). %C A089105 19, 22, 23, 26, 29, 31, 34, 37, 38, 41, 43, 46, and 47 are in this sequence. Is this a duplicate of A007916? - _Charles R Greathouse IV_, Sep 07 2011 %C A089105 Comment from _Don Reble_, May 27 2014 (Start): %C A089105 It has because of %C A089105 ------ ---------------------------- %C A089105 18 565491872244422701441 %C A089105 20 76786041519852770748961 %C A089105 21 1747624437573692208710761 %C A089105 24 79962397898771029747829041 %C A089105 Alas, those are merely upper-bounds on the A089825 values. %C A089105 (End) %C A089105 The least witness function W(k) is defined for odd composite numbers k. The sequence W(k) does not have its own entry in the OEIS because W(k) = 2 for all k with 9 <= k < 2047; then W(2047)=3. - _N. J. A. Sloane_, Sep 16 2014 %C A089105 Is this related to A341646? - _R. J. Mathar_, Jul 07 2023 %D A089105 R. Crandall and C. Pomerance, Prime Numbers: A Computational Perspective, Springer, NY, 2001; see p. 157 (pp. 168f in the 2nd edition). %H A089105 W. R. Alford, A. Granville, and C. Pomerance (1994). "<a href="http://www.math.dartmouth.edu/~carlp/PDF/reliable.pdf">On the difficulty of finding reliable witnesses</a>". Lecture Notes in Computer Science 877, 1994, pp. 1-16. %H A089105 Balasubramanian, R., and S. V. Nagaraj. <a href="https://doi.org/10.1007/BFb0030409">The least witness of a composite number</a>, In Information Security, LNCS 1396 (1998), pp. 66-74. %Y A089105 Cf. A089825, A007916. %K A089105 nonn,hard %O A089105 1,1 %A A089105 _N. J. A. Sloane_, Jan 18 2004 %E A089105 Missing values a(11) and a(14) added by _Charles R Greathouse IV_, Sep 07 2011, based on Sep 24 2010 SeqFan posting %E A089105 a(13)-a(20) from _Charles R Greathouse IV_, May 27 2014 based on comments from _Charles R Greathouse IV_ and _Don Reble_