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A209878 RATS: Reverse Add Then Sort the digits applied to previous term, starting with 20169. 7
20169, 111267, 337788, 1122255, 4446666, 1111113, 2222244, 4446666, 1111113, 2222244, 4446666, 1111113, 2222244, 4446666, 1111113, 2222244, 4446666, 1111113, 2222244, 4446666, 1111113, 2222244, 4446666, 1111113, 2222244, 4446666, 1111113, 2222244, 4446666 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A114613(1) = 20169 is the smallest starting number for a RATS trajectory leading to a cycle of length 3: A114611(20169) = 3;

a(n + 3) = a(n) for n > 4.

LINKS

Table of n, a(n) for n=1..29.

Eric Weisstein's World of Mathematics, RATS Sequence

Index entries for linear recurrences with constant coefficients, signature (0, 0, 1).

FORMULA

a(n + 1) = A036839(a(n)).

MATHEMATICA

Join[{20169, 111267, 337788, 1122255}, LinearRecurrence[{0, 0, 1}, {4446666, 1111113, 2222244}, 25]] (* Ray Chandler, Aug 25 2015 *)

PROG

(Haskell)

a209878 n = a209878_list !! (n-1)

a209878_list = iterate a036839 20169

CROSSREFS

Cf. A004000, A066710, A066711, A209879, A209880.

Sequence in context: A235520 A235651 A114613 * A031682 A052358 A052189

Adjacent sequences:  A209875 A209876 A209877 * A209879 A209880 A209881

KEYWORD

nonn,base

AUTHOR

Reinhard Zumkeller, Mar 14 2012

STATUS

approved

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Last modified July 16 04:26 EDT 2019. Contains 325064 sequences. (Running on oeis4.)