|
%I #20 Jun 23 2018 13:54:32
%S 1,3,6,111,353,7557,2376732
%N Palindromes that are the sum of the first n palindromes for some n.
%C No additional terms up through the partial sums of all palindromes less than or equal to 10^7-1. - _Harvey P. Dale_, Jun 23 2018
%H P. De Geest, <a href="http://www.worldofnumbers.com/index.html">World!Of Numbers</a>
%F a(n) = A046489(A046486(n)-1). - _R. J. Mathar_, Sep 09 2015
%e a(4) = 111 as 111 = 1+2+3+4+5+6+7+8+9+11+22+33.
%t palQ[n_] := Reverse[x = IntegerDigits[n]] == x; Select[Accumulate[Select[Range[25000], palQ]], palQ] (* _Jayanta Basu_, Jun 26 2013 *)
%t Select[Accumulate[Select[Range[10^6],PalindromeQ]],PalindromeQ] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jun 23 2018 *)
%Y Cf. A002113, A046486, A046487.
%K nonn,hard,base
%O 1,2
%A _Patrick De Geest_, Sep 15 1998
%E Edited by _Jonathan Sondow_, Nov 28 2017
| 