%I #5 Mar 30 2012 18:57:12
%S 2,3,4,5,6,7,8,10,11,12,13,14,15,16,17,18,19,20,21,22,23,25,26,27,28,
%T 29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,47,48,49,50,51,52,
%U 53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105
%N Complement of the 9-gonal numbers.
%F a(n)=n+Floor[1/2+(2n/7)^(1/2)].
%t Table[n+Floor[1/2+(2n/7)^(1/2)], {n,100}]
%Y Cf. A001106 (9-gonal numbers).
%K nonn
%O 1,1
%A _Clark Kimberling_, Jan 01 2011
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