%I #55 Apr 15 2019 16:35:13
%S 1,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,
%T 97,101,103,107,109,113,127,131,137,139,149,151,157,163,167,173,179,
%U 181,191,193,197,199,211,223,227,229,233,239,241,251,257,263,269,271
%N The odd prime numbers together with 1.
%C The odd noncomposite numbers. Also odd primes at the beginning of the 20th century. - _Omar E. Pol_, Mar 19 2008
%C Indices at which records occur in A002322. - _Artur Jasinski_, Apr 05 2008
%C Odd numbers n such that their largest divisor <= sqrt(n) equals 1. (See A161344). - _Omar E. Pol_, Aug 03 2009
%C All k for which cos((k-1)!*Pi/k) is negative. - _Gerry Martens_, Jun 01 2018
%H 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, p. 870 [alternative scanned copy].
%H S. M. Losanitsch, <a href="/A000602/a000602_1.pdf">Die Isomerie-Arten bei den Homologen der Paraffin-Reihe</a>, Chem. Ber. 30 (1897), 1917-1926. (Annotated scanned copy)
%F a(n) = A000040(n) - A000007(n) = A000040(n) - ((-1)^A000040(n)+1)/2. - _Juri-Stepan Gerasimov_, Oct 25 2009
%F a(n) = A175524(n) for n <= 30. - _Reinhard Zumkeller_, Jul 12 2011
%t a = {}; max = 0; Do[w = CarmichaelLambda[k]; If[w > max, AppendTo[a, k]; max = k], {k, 1, 200}]; a (* _Artur Jasinski_, Apr 05 2008 *)
%t Join[{1},Prime[Range[2,60]]] (* _Harvey P. Dale_, Apr 15 2019 *)
%o (PARI) prime(n)-(n==1) \\ _Charles R Greathouse IV_, Aug 26 2011
%Y Cf. A000040, A008578, A065091, A002322.
%K nonn,easy
%O 1,2
%A _N. J. A. Sloane_