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A335702
A sequence connected with Rado’s explicit description of the Erdős-Rényi countable random graph.
2
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
1,3
COMMENTS
It would be nice to have an explicit definition.
LINKS
Peter J. Cameron, A Puzzle, Blog, Aug 05 2020.
Peter J. Cameron, Puzzle Solution, Blog, Aug 13 2020.
PROG
(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
CROSSREFS
Cf. A133457.
Sequence in context: A035001 A260386 A092268 * A069259 A102186 A039842
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Aug 13 2020
EXTENSIONS
More terms from Rémy Sigrist, Aug 14 2020
STATUS
approved