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A228199 Smallest of 7 consecutive primes whose sum is not a prime. 1

%I

%S 2,3,5,7,11,13,37,41,59,67,73,83,101,109,131,139,149,157,163,167,173,

%T 179,181,191,193,197,199,211,223,227,229,239,241,251,263,269,271,277,

%U 281,283,293,307,311,331,337,347,349,353,389,397,409,419,421,431,433,439,443

%N Smallest of 7 consecutive primes whose sum is not a prime.

%H Vincenzo Librandi, <a href="/A228199/b228199.txt">Table of n, a(n) for n = 1..1000</a>

%e 59 is in the sequence because 59+61+67+71+73+79+83 = 493 and 493 is not a prime.

%t Transpose[Select[Partition[Prime[Range[150]], 7, 1], ! PrimeQ[Total[#]] &]][[1]]

%t Prime[Select[Range[100], ! PrimeQ[Sum[Prime[# + i], {i, 0, 6}]] &]] (* _Bruno Berselli_, Aug 22 2013 *)

%o (MAGMA) [NthPrime(n): n in [1..120] |not IsPrime(&+[NthPrime(n+s): s in [0..6]])];

%Y Cf. A000040, A180948.

%K nonn

%O 1,1

%A _Vincenzo Librandi_, Aug 20 2013

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Last modified January 23 10:50 EST 2020. Contains 331171 sequences. (Running on oeis4.)