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A085309 Initial values providing nontrivial cyclic attractor when function defined in A085307 is iterated. 4
213, 323, 639, 713 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..4.

FORMULA

Algorithm: 1# factorize n; 2# arrange prime-factors by decreasing size; 3# concatenate prime factors and interpret the result as decimal number.Iterate 1#, 2#, 3#.

EXAMPLE

n=213 gives {213,713,3123,3473,15123,713},

n=323 gives {323,1917,713,3123,3473,15123,713}

n=639 gives {639,713,3123,3473,15123,713}

CROSSREFS

Cf. A084317-A084319, A085308, A085309.

Sequence in context: A252025 A238019 A251146 * A252024 A302256 A092127

Adjacent sequences:  A085306 A085307 A085308 * A085310 A085311 A085312

KEYWORD

base,nonn

AUTHOR

Labos Elemer, Jun 27 2003

STATUS

approved

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Last modified November 29 21:32 EST 2021. Contains 349416 sequences. (Running on oeis4.)