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%I #15 Sep 08 2022 08:46:05
%S 2,5,7,11,13,17,19,23,41,43,53,59,61,67,71,73,97,101,103,113,137,151,
%T 163,167,181,191,223,227,229,233,239,251,257,263,269,271,281,283,293,
%U 307,311,313,317,331,337,349,353,379,383,401,409,419,421,431,439,443,457,461
%N Smallest of 9 consecutive primes whose sum is not a prime.
%H Vincenzo Librandi, <a href="/A228200/b228200.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 + 89 + 97 = 679 and 679 is not a prime.
%t Transpose[Select[Partition[Prime[Range[150]], 9, 1], !PrimeQ[Total[#]]&]][[1]]
%o (Magma) [NthPrime(n): n in [1..120] |not IsPrime(&+[NthPrime(n+s): s in [0..8]])];
%Y Cf. A189571, A127336.
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Aug 20 2013