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a(n) = a(n-1) + c(n) for n >= 3, a( ) increasing, given a(1)=3 a(2)=6; where c( ) is complement of a( ).
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%I #13 Apr 05 2016 10:46:46

%S 3,6,10,15,22,30,39,50,62,75,89,105,122,140,159,179,200,223,247,272,

%T 298,325,353,382,413,445,478,512,547,583,620,658,698,739,781,824,868,

%U 913,959,1006,1054,1103,1154,1206,1259,1313,1368,1424,1481,1539

%N a(n) = a(n-1) + c(n) for n >= 3, a( ) increasing, given a(1)=3 a(2)=6; where c( ) is complement of a( ).

%C Here "complement" refers to the numbers not in the sequence.

%C Essentially the same as A022949. [_R. J. Mathar_, Oct 25 2008]

%H Ivan Neretin, <a href="/A022952/b022952.txt">Table of n, a(n) for n = 1..10000</a>

%t Fold[Append[#1, #1[[-1]] + Complement[Range[Max@#1 + 3], #1][[#2]]] &, {3, 6}, Range[3, 50]] (* _Ivan Neretin_, Apr 05 2016 *)

%Y Cf. A005228 and references therein.

%K nonn

%O 1,1

%A _Clark Kimberling_