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%I #29 Sep 19 2015 15:41:28
%S 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,22,23,24,25,26,
%T 27,28,29,30,31,33,34,35,36,37,38,39,40,41,42,44,45,46,47,48,49,50,51,
%U 52,53,55,56,57,58,59,60,61,62,63,64,66,67,68,69,70,71,72,73,74,75,77,78,79,80,81,82,83,84,85,86,88,89,90,91,92,93,94,95,96,97,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120
%N Numbers that can be written as the sum of two nonnegative palindromes in base 10.
%C More than the usual number of terms are shown in order to distinguish this from A261906. - _N. J. A. Sloane_, Sep 09 2015
%C A260254(a(n)) > 0.
%H Reinhard Zumkeller, <a href="/A260255/b260255.txt">Table of n, a(n) for n = 1..10000</a>
%H Chai Wah Wu, <a href="/A260255/a260255.pdf">Fraction of first n numbers that are terms of this sequence, for n < 10^8</a>, Sep 15 2015
%t palQ[n_Integer, base_Integer] := Block[{}, Reverse[idn = IntegerDigits[n, base]] == idn]; Take[ Union[ Plus @@@ Tuples[ Select[ Range[0, 100], palQ[#, 10] &], 2]], 90] (* _Robert G. Wilson v_, Jul 22 2015 *)
%o (Haskell)
%o a260255 n = a260255_list !! (n-1)
%o a260255_list = filter ((> 0) . a260254) [0..]
%Y Cf. A035137 (complement), A260254, A002113.
%Y 111 is a member of this sequence but not of A261906. A213879 lists the differences.
%K nonn,base
%O 1,3
%A _Reinhard Zumkeller_, Jul 21 2015