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Greatest prime p such that p can be expressed as the sum of consecutive primes with largest prime in the sum = n-th prime.
4

%I #6 Apr 10 2013 10:55:22

%S 2,5,5,17,23,41,53,67,83,127,83,197,233,281,311,379,311,499,563,479,

%T 431,733,857,953,1019,1151,1259,1361,1439,1583,1523,1823,1607,2099,

%U 1637,2417,2579,2719,2909,2927,3137,3389,3257,3821,3527,4217,4421,4651,4871

%N Greatest prime p such that p can be expressed as the sum of consecutive primes with largest prime in the sum = n-th prime.

%H Donovan Johnson, <a href="/A082534/b082534.txt">Table of n, a(n) for n = 1..1000</a>

%e For n=10; 29 is the 10th prime, largest prime in the sum = 29. 29=29, 71=19+23+29, 101=13+17+19+23+29, 127=3+5+7+11+13+17+19+23+29. 29 and 71,101,127 are primes. 127 is the greatest prime, so a(10)=127.

%o (PARI) for(n=1, 1000, s=0; forstep(j=n, 1, -1, s=s+prime(j); if(isprime(s), p=s)); write("b082534.txt", n " " p)) /* _Donovan Johnson_, Apr 10 2013 */

%K easy,nonn

%O 1,1

%A _Naohiro Nomoto_, May 02 2003