A335702 A sequence connected with Rado’s explicit description of the Erdős-Rényi countable random graph.

0, 1, 2, 4, 5, 8, 12, 16, 17, 18, 24, 32, 34, 40, 48, 50, 56, 64, 65, 72, 80, 81, 88, 96, 104, 112, 120, 128, 136, 144, 152, 160, 168, 176, 184, 192, 200, 208, 216, 224, 232, 240, 248, 256, 257, 258, 260, 261, 272, 273, 274, 288, 290, 304, 306, 320, 321, 336

Offset: 1

Author

N. J. A. Sloane, Aug 13 2020

Keywords

• nonn

Comments

It would be nice to have an explicit definition.

Links

• Rémy Sigrist, Table of n, a(n) for n = 1..10000
• Peter J. Cameron, A Puzzle, Blog, Aug 05 2020.
• Peter J. Cameron, Puzzle Solution, Blog, Aug 13 2020.

Crossrefs

Cf. A133457.

Programs

PARI

S(n) = { my (s=[], i); while (n, i=valuation(n,2); s=concat(s,i); n-=2^i); s }
is(n) = my (s=S(n), z=if (#s, Set(concat(apply(S, s))), [])); setintersect(s, z)==[] \\ Rémy Sigrist, Aug 14 2020

Extensions

More terms from Rémy Sigrist, Aug 14 2020