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%I #11 Jun 19 2018 03:28:21
%S 2069,2159,2249,2339,2429,2519,2609,2699,2789,2879,2969,3068,3158,
%T 3248,3338,3428,3518,3608,3698,3788,3878,3968,4067,4157,4247,4337,
%U 4427,4517,4607,4697,4787,4877,4967,5066,5156,5246,5336,5426,5516,5606,5696,5786
%N Numbers from which 12 'Reverse and Add' steps are needed to reach a palindrome.
%C The number of steps starts at 0, so palindromes (cf. A002113) are excluded. This sequence coincides with the corresponding sequence not excluding palindromes (A015993) for the entries shown in the database. The first divergence occurs at 10901.
%H Harry J. Smith, <a href="/A065217/b065217.txt">Table of n, a(n) for n = 1..1000</a>
%H <a href="/index/Res#RAA">Index entries for sequences related to Reverse and Add!</a>
%o (PARI) Rev(x)= { local(d, r=0); while (x>0, d=x-10*(x\10); x\=10; r=r*10 + d); return(r) } digitsIn(x)= { local(d); if (x==0, return(1)); d=1 + log(x)\log(10); if (10^d == x, d++, if (10^(d-1) > x, d--)); return(d) } Palin(x)= { local(d,e,f,i,t,y); if (x==0, return(1)); y=x; d=digitsIn(x); t=10^(d - 1); for (i=1, d\2, f=y-10*(y\10); y\=10; e=x\t; x-=t*e; t/=10; if (e!=f, return(0)) ); return(1) } { n=0; for (m = 0, 10^9, p=m; b=1; for (i=1, 12, if (Palin(p), b=0; break); p=Rev(p) + p); if (b && Palin(p), write("b065217.txt", n++, " ", m); if (n==1000, return)) ) } \\ _Harry J. Smith_, Oct 14 2009
%Y Cf. A002113, A015993, A065206.
%K nonn,base
%O 1,1
%A _Klaus Brockhaus_, Oct 21 2001
%E Offset changed from 0 to 1 by _Harry J. Smith_, Oct 14 2009
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