A186083 Values taken by A161903, sorted and duplicates removed.

0, 3, 6, 7, 12, 13, 14, 15, 24, 25, 26, 27, 28, 30, 31, 48, 49, 50, 51, 52, 54, 55, 56, 59, 60, 61, 62, 63, 96, 97, 98, 99, 100, 102, 103, 104, 107, 108, 109, 110, 111, 112, 115, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 192, 193, 194, 195, 196, 198, 199

Offset: 1

Author

Ben Branman, Feb 12 2011

Keywords

• nonn

Comments

The sequence contains 2k if and only if it contains k.

If the binary expansion of n has k bits, then A161903(n) will have k+1 bits. Thus, to determine if a number with m bits belongs to the sequence, it is sufficient to check A161903(i) up to i=2^(m-1)-1.

Links

• T. D. Noe, Table of n, a(n) for n = 1..1309
• Index entries for sequences related to cellular automata
• Eric Weisstein's World of Mathematics, Rule 110

Crossrefs

Cf. A161903.

Programs

Mathematica

f[n_] := FromDigits[Drop[Part[CellularAutomaton[110, {IntegerDigits[n, 2], 0}], 1], -1], 2]; Union[Table[f[n], {n, 0, 2047}]]