%I #14 Jan 10 2024 20:07:39
%S 1,3,3,5,6,8,9,11,12,13,18,19,20,26,27,31,35,37,39,46,48,50,59,61,63,
%T 73,75,78,88,91,94,105,108,111,124,127,130,144,147,151,165,169,173,
%U 188,192,196,213,217,221,239,243,248,266,271,276,295,300,305,326
%N Covering numbers C(n,4,2).
%C Only differs from A240115 when n = 7, 9, 10, or 19. - _Nathaniel Johnston_, Jan 10 2024
%D CRC Handbook of Combinatorial Designs, 1996, p. 262.
%H D. Gordon, <a href="http://www.dmgordon.org/cover">La Jolla Repository of Coverings</a>
%H <a href="/index/Cor#covnum">Index entries for covering numbers</a>
%Y Cf. A011975, A011977.
%K nonn,easy
%O 4,2
%A _N. J. A. Sloane_.
%E a(21)-a(62) from _Nathaniel Johnston_, Jan 10 2024