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A184415
Lower s(n)-Wythoff sequence, where s(n)=floor[(n+2)/3]. Complement of A184416.
4
1, 3, 5, 7, 8, 11, 12, 14, 16, 18, 20, 21, 23, 26, 27, 29, 30, 33, 34, 37, 38, 40, 42, 43, 46, 47, 49, 52, 53, 54, 57, 59, 60, 61, 65, 66, 67, 69, 72, 74, 75, 76, 79, 81, 83, 84, 86, 87, 91, 92, 93, 95, 97, 99, 101, 104, 105, 106, 107, 111, 112, 114, 116, 118, 119, 121, 122, 125, 128, 129, 130, 132, 134, 136, 138, 139, 142, 144, 146, 147, 149, 150, 152, 155, 157, 158, 160, 162, 164, 166, 167, 169, 171, 172, 175, 177, 179, 181, 182, 184
OFFSET
1,2
EXAMPLE
s=(1,1,1,2,2,2,3,3,3,4,4,4,5,5,5,...)=A002264.
a=(1,3,5,7,8,11,12,14,16,18,20,...)=A184415.
b=(2,4,6,9,10,13,15,17,19,22,24,...)=A184416.
Briefly: s=a+b, where a=mex="least missing".
MATHEMATICA
mex:=First[Complement[Range[1, Max[#1]+1], #1]]&;
s[n_]:=Floor[(n+2)/3]; a[1]=1; b[n_]:=b[n]=s[n]+a[n];
a[n_]:=a[n]=mex[Flatten[Table[{a[i], b[i]}, {i, 1, n-1}]]];
Table[s[n], {n, 20}]
Table[a[n], {n, 100}]
Table[b[n], {n, 100}]
CROSSREFS
Sequence in context: A190719 A187224 A106252 * A050111 A090542 A260518
KEYWORD
nonn
AUTHOR
Clark Kimberling, Jan 13 2011
STATUS
approved