A183213 Ordering of the numbers in the set S generated by these rules: 1 is in S, and if n is in S, then floor[(3n-1)/2] and 3n are in S.

1, 3, 4, 5, 7, 9, 10, 12, 13, 14, 15, 17, 19, 20, 21, 22, 25, 27, 28, 29, 30, 31, 32, 36, 37, 39, 40, 41, 42, 43, 44, 45, 46, 47, 51, 53, 55, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 70, 75, 76, 79, 81, 82, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 100, 101, 104, 108, 111, 112, 113, 117, 118, 120, 121, 122, 123, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135

Offset

1,2

Comments

This sequence results from flattening and sorting the tree at A183211. Complement of A178931, obtained from the tree at A183212.

Links

Ivan Neretin, Table of n, a(n) for n = 1..10000

Formula

(See the Mathematica code.)

Mathematica

nn=200; t={1}; t0=t; While[t=Select[Union[t, Floor[(3*t-1)/2], 3*t], #<=nn &]; t0 != t, t0=t]; t
f[s_List] := Select[ Union@ Join[s, Floor[(3 s - 1)/2], 3 s], # < 201 &]; NestWhile[f, {1}, UnsameQ, All]

Crossrefs

Cf. A183211, A178931.

Sequence in context: A213637 A047251 A258932 * A183172 A136495 A184419

Adjacent sequences: A183210 A183211 A183212 * A183214 A183215 A183216

Keyword

nonn

Author

Clark Kimberling, Dec 30 2010

Status

approved