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 A083664 a(1) = 1, a(n) = if n mod 10 = 0 then n else smallest number m, not occurring earlier such that m*a(n-d) is a palindrome, where d = if n mod 10 = 1 then 2 else 1. 3

%I

%S 1,2,3,11,4,22,28,9,19,10,17,16,29,8,34,88,7,23,18,20,14,31,154,13,38,

%T 231,12,21,25,30,209,42,6,37,15,35,143,49,77,40,26,33,47,303,57,333,

%U 64,66,32,50,132,48,44,53,404,58,364,111,5,60,101,55,91,99,46,437,92,236

%N a(1) = 1, a(n) = if n mod 10 = 0 then n else smallest number m, not occurring earlier such that m*a(n-d) is a palindrome, where d = if n mod 10 = 1 then 2 else 1.

%C Permutation of natural numbers: a(A083665(n))=A083665(a(n))=n;

%C for n>1: a(n)=n iff n == 0 modulo 10.

%H <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>

%Y Cf. A083666, A083125, A002113.

%K nonn,base

%O 1,2

%A _Reinhard Zumkeller_, May 02 2003

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Last modified September 22 03:54 EDT 2020. Contains 337289 sequences. (Running on oeis4.)