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A094658 Smallest number which requires n iterations to reach a prime when iterating x + sum of squares of digits of x. 0
1, 48, 28, 6, 9, 4, 33, 30, 22, 54, 8, 26, 21, 112, 92, 80, 27, 64, 972, 878, 805, 669, 576, 484, 377, 291, 253, 1629, 6591, 6474, 6289, 6167, 5976, 5853, 5697, 5558, 5456, 5492, 5379, 5282, 5183, 4986, 4936, 4790, 4666, 4489, 4384, 4284, 4416, 6183, 5992, 21693 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..52.

EXAMPLE

a(3)=28 because 28 takes 3 iterations to reach a prime: 28 -> 96 -> 213 -> 227.

CROSSREFS

Sequence in context: A033368 A128380 A298451 * A136455 A085517 A299525

Adjacent sequences:  A094655 A094656 A094657 * A094659 A094660 A094661

KEYWORD

base,nonn

AUTHOR

Jason Earls, Jun 14 2004

STATUS

approved

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Last modified October 21 10:39 EDT 2021. Contains 348150 sequences. (Running on oeis4.)