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Palindromes that are the sum of consecutive initial primes.
3

%I #20 Sep 01 2018 09:14:59

%S 2,5,77,285080582,352888253,854848458,137372273731,2939156519392,

%T 6833383883833386,27155268786255172,477749724515427947774,

%U 625179415050514971526,714014821826628128410417,2719564270866680724659172

%N Palindromes that are the sum of consecutive initial primes.

%C a(15) > 1.22*10^26. - _Giovanni Resta_, Sep 01 2018

%H C. Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_007.htm">Source</a>

%e 2+3+5+7+11+13+17+19 = 77.

%o (PARI)

%o rev(n)=r="";d=digits(n);for(i=1,#d,r=concat(Str(d[i]),r));eval(r)

%o s=0;for(n=1,10^5,s+=prime(n);if(rev(s)==s,print1(s,", "))) \\ _Derek Orr_, Aug 16 2014

%Y Cf. A007504, A038582, A038584, A058847.

%K nonn,base,more

%O 1,1

%A _Jud McCranie_

%E a(11)-a(12) from _Donovan Johnson_, Apr 25 2010

%E a(13)-a(14) from _Giovanni Resta_, Aug 30 2018