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A053169 A paradoxical sequence: a positive integer n is in this sequence if and only if n is not in sequence A_n in the database. 1
4, 7, 9, 11, 12, 13, 15, 17, 18, 20, 21, 22, 23, 24, 25, 28, 29, 30, 31, 32, 33, 34, 35, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 53, 54, 55, 56, 57, 58, 60, 61, 63, 64, 65, 66, 67, 68, 70, 71, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

"Not in sequence A_n" means not in the full list of terms, not simply in the list of terms visible in the entry.

The paradox is of course: is 53169 in this sequence?

Is 53873 in this sequence? - Tanya Khovanova, Aug 09 2007

REFERENCES

Smullyan, Raymond M, What is the name of this book? : The riddle of Dracula and other logical puzzles, Englewood Cliffs, NJ : Prentice-Hall, c1978, see puzzle 163.

LINKS

Table of n, a(n) for n=1..81.

EXAMPLE

Sequence A000001 contains 1, so 1 is not in the sequence; A000002 contains 2, so 2 is not in the sequence; ...

CROSSREFS

Cf. A037181.

Complement of A053873.

Sequence in context: A234429 A153001 A010454 * A007656 A159619 A207017

Adjacent sequences:  A053166 A053167 A053168 * A053170 A053171 A053172

KEYWORD

nonn,nice

AUTHOR

Miklos Szabo (mike(AT)ludens.elte.hu), N. J. A. Sloane, Tue Feb 29 2000

EXTENSIONS

Thanks to Alexander Hulpke (ahulpke(AT)math.ohio-state.edu) for the information that 19 is in A000019.

Extended to n=100 by N. J. A. Sloane, May 26 2007

STATUS

approved

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Last modified December 18 17:57 EST 2014. Contains 252173 sequences.