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A117230 Start with 1 and repeatedly reverse the digits and add 1 to get the next term. 7
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 2, 3, 4, 5, 6, 7, 8, 9, 10, 2, 3, 4, 5, 6, 7, 8, 9, 10, 2, 3, 4, 5, 6, 7, 8, 9, 10, 2, 3, 4, 5, 6, 7, 8, 9, 10, 2, 3, 4, 5, 6, 7, 8, 9, 10, 2, 3, 4, 5, 6, 7, 8, 9, 10, 2, 3, 4, 5, 6, 7, 8, 9, 10, 2, 3, 4, 5, 6, 7, 8, 9, 10, 2, 3, 4, 5, 6, 7, 8, 9, 10, 2, 3, 4, 5, 6, 7, 8, 9, 10 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..100.

N. J. A. Sloane and others, Sequences of RADD type, OEIS wiki.

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

FORMULA

Has period 9.

a(n)=2+[(n-2) mod 9]-9*(C[2*(n-1),n-1] mod 2), with n>=1. - Paolo P. Lava, Oct 21 2008

G.f.: -x*(9*x^9 +9*x^8 +8*x^7 +7*x^6 +6*x^5 +5*x^4 +4*x^3 +3*x^2 +2*x +1) / ((x -1)*(x^2 +x +1)*(x^6 +x^3 +1)). - Colin Barker, May 23 2014

MAPLE

read transforms; t1:=[1]; for n from 1 to 80 do t1:=[op(t1), 1+digrev(t1[n])]; od:

MATHEMATICA

Join[{1}, LinearRecurrence[{0, 0, 0, 0, 0, 0, 0, 0, 1}, {2, 3, 4, 5, 6, 7, 8, 9, 10}, 99]] (* Ray Chandler, Jul 18 2015 *)

PROG

(PARI) a(n)=if(n>1, (n-2)%9+2, 1) \\ M. F. Hasler, May 22 2014

CROSSREFS

Cf. A117830, A117521, A117828, A117800, A117816, A117817.

Sequence in context: A056960 A227362 A103693 * A093882 A138953 A053392

Adjacent sequences:  A117227 A117228 A117229 * A117231 A117232 A117233

KEYWORD

nonn,base,easy

AUTHOR

N. J. A. Sloane, following discussions with Luc Stevens, May 04 2006

EXTENSIONS

Correction to the terms of the sequence (inserted missing term) Jeremy Gardiner, Jun 17 2010

STATUS

approved

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Last modified November 21 17:44 EST 2017. Contains 295004 sequences.