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A098740
Start with the sequence of natural numbers S(0)={1,2,3,...} and define, for i>0, S(i)=D(i)S(i-1), where D(i)A denotes the operation of deleting the a(1+[i/2])th term of A={a(1),a(2),a(3),...}. E.g. D(3){1,2,4,6,9,10,...} means to delete the a(1+[3/2])th = 2nd term of {1,2,4,9,10,...}, giving {1,4,9,10,...}. The given sequence is the limit of S(i) as i->inf.
1
2, 3, 6, 7, 8, 11, 14, 17, 18, 19, 22, 23, 24, 27, 28, 29, 32, 35, 38, 39, 40, 43, 46, 49, 50, 51, 54, 57, 60, 61, 62, 65, 66, 67, 70, 71, 72, 75, 78, 81, 82, 83, 86, 87, 88, 91, 92, 93, 96, 99, 102, 103, 104, 107, 108, 109, 112, 113, 114, 117, 120, 123, 124, 125, 128, 131
OFFSET
1,1
COMMENTS
It appears that the first difference sequence of {a(n)} is A080426.
EXAMPLE
D(1){1,2,3,4,5,6,...}={2,3,4,5,6,7,...} (delete first term),
D(2){2,3,4,5,6,7,...}={2,3,5,6,7,8,...} (delete 3rd term),
D(3){2,3,5,6,7,8,9,...}={2,3,6,7,8,9,...} (delete 3rd term),
D(4){2,3,6,7,8,9,10,...}={2,3,6,7,8,10,...} (delete 6th term),
...
Limiting case: {a(n)}.
CROSSREFS
Cf. A080426.
Sequence in context: A097757 A304028 A155152 * A116046 A069579 A327176
KEYWORD
nonn
AUTHOR
John W. Layman, Oct 29 2004
STATUS
approved