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%I #21 Sep 11 2018 03:10:43
%S 1,2,3,4,5,6,7,8,9,10,10,11,11,11,11,11,11,11,11,11,11,11,12,12,12,12,
%T 12,12,12,12,12,12,12,13,13,13,13,13,13,13,13,13,13,13,14,14,14,14,14,
%U 14,14,14,14,14,14,15,15,15,15,15,15,15,15,15,15,15,16,16,16,16,16,16,16,16,16
%N Number of palindromes in the range [0,n] inclusive.
%C Partial sums of A136522. [Typo fixed by _Colin Barker_, Apr 26 2015]
%H N. J. A. Sloane, <a href="/A136687/b136687.txt">Table of n, a(n) for n = 0..20202</a>
%F a(n) = inv_A002113(A261423(n)), where inv_A002113 is the inverse of A002113, i.e., it yields the index of a palindrome. - _M. F. Hasler_, Sep 10 2018
%t palQ[n_]:=Module[{idn=IntegerDigits[n]},idn==Reverse[idn]]; Accumulate[ Table[ If[palQ[n],1,0],{n,0,80}]] (* _Harvey P. Dale_, May 11 2014 *)
%o (PARI) A136687(n)=inv_A002113(A261423(n)) \\ _M. F. Hasler_, Sep 09 2018
%Y Cf. A002113, A136522, A137180, A261423.
%K nonn,base
%O 0,2
%A _N. J. A. Sloane_, Apr 21 2008
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