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A180124 Third of three "least, sum, least" self-generating sequences. 3
3, 5, 8, 11, 14, 16, 19, 22, 24, 27, 30, 33, 35, 38, 41, 44, 46, 49, 52, 55, 57, 60, 63, 65, 68, 71, 74, 76, 79, 82, 85, 87, 90, 93, 95, 98, 101, 104, 106, 109, 112, 115, 117, 120, 123, 126, 128, 131, 134, 136, 139, 142, 145, 147, 150, 153, 156, 158, 161, 164, 167 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Clark Kimberling, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = least positive integer not yet used;

b(n) = n + a(n);

c(n) = least positive integer not yet used.

EXAMPLE

The three sequences, labeled a,b,c, are

a=(1,4,7,9,...), b=(2,6,10,13,...), c=(3,5,8,11...).

MATHEMATICA

mex[list_, offset_]:=NestWhile[#+1&, offset, MemberQ[list, #]&];

z=100; a[1]=1; b[1]=1+a[1];

c[1]=mex[soFar={a[1], b[1]}, 1];

Do[soFar=Join[soFar, {c[n-1]}];

    a[n]=mex[soFar, c[n-1]];

    b[n]=n+a[n]; soFar=Join[soFar, {a[n], b[n]}];

    c[n]=mex[soFar, a[n]], {n, 2, z}]

Map[a, Range[z]](*A180122*)

Map[b, Range[z]](*A180123*)

Map[c, Range[z]](*A180124*)

(* Peter J. C. Moses, Aug 22 2014 *)

A180122 = Map[Floor[(1 + Sqrt[3]) #] - 1 &, Range[200]]

A180123 = A180122 + Range[200]

A180124 = Complement[Range[Last[A180122]], Flatten[{A180122, A180123}]]

(* Peter J. C. Moses, Aug 23 2014 *)

CROSSREFS

Cf. A180122, A180123.

Sequence in context: A079392 A185723 A022852 * A095375 A129260 A076829

Adjacent sequences:  A180121 A180122 A180123 * A180125 A180126 A180127

KEYWORD

nonn

AUTHOR

Clark Kimberling, Aug 11 2010

STATUS

approved

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Last modified November 24 18:11 EST 2020. Contains 338616 sequences. (Running on oeis4.)