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A204540 Numbers n with property that their basins (as defined in A204539) equal 1. 2
2, 3, 4, 6, 14, 1760, 39046 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Only seven such numbers are known. Referring back to A204539, we cannot be certain that these are the only numbers with the property basin(n) = 1, but there are no others for n less than 12,000,000.  Furthermore the average value of basin(n) is approximately equal to n/3 for large values of n, which makes it extremely unlikely that another one will ever be found.

For unknown reasons, all integers >5 with basin equal to 1 or 2 are even.  See A185001 for the list of known numbers with basin = 2.

LINKS

Table of n, a(n) for n=1..7.

MATHEMATICA

(* First run the program for A204539 to define basin *) Select[Range[1000], basin[#] == 1 &]] (* Alonso del Arte, Jan 19 2012 *)

CROSSREFS

Cf. A204539, A185001

Sequence in context: A293714 A049911 A056712 * A280592 A330990 A337129

Adjacent sequences:  A204537 A204538 A204539 * A204541 A204542 A204543

KEYWORD

nonn

AUTHOR

Colm Fagan, Jan 16 2012

STATUS

approved

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Last modified October 24 10:40 EDT 2021. Contains 348225 sequences. (Running on oeis4.)