A046488 - OEIS

A046488

Palindromes that are the sum of the first n palindromes for some n.

1, 3, 6, 111, 353, 7557, 2376732

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OFFSET

1,2

COMMENTS

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

LINKS

FORMULA

a(n) = A046489(A046486(n)-1). - R. J. Mathar, Sep 09 2015

EXAMPLE

a(4) = 111 as 111 = 1+2+3+4+5+6+7+8+9+11+22+33.

MATHEMATICA

palQ[n_] := Reverse[x = IntegerDigits[n]] == x; Select[Accumulate[Select[Range[25000], palQ]], palQ] (* Jayanta Basu, Jun 26 2013 *)

Select[Accumulate[Select[Range[10^6], PalindromeQ]], PalindromeQ] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jun 23 2018 *)

CROSSREFS

KEYWORD

nonn,hard,base

AUTHOR

EXTENSIONS

Edited by Jonathan Sondow, Nov 28 2017

STATUS

approved