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Numbers n such that the sum of the first n primes with the final digit 9 is prime.
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%I #5 Aug 23 2017 16:10:24

%S 1,3,7,11,13,19,37,39,61,73,89,107,109,113,117,147,153,159,171,173,

%T 207,241,253,307,311,329,347,419,429,461,481,491,497,509,523,529,539,

%U 543,559,613,617,631,651,691,701,703,731,737,741,753,799,809,813,823,827

%N Numbers n such that the sum of the first n primes with the final digit 9 is prime.

%F a(n)=primes in A030433 added to obtain A129081(n)

%t Position[Accumulate[Select[Prime[Range[5000]],Last[ IntegerDigits[#]] == 9&]],_?PrimeQ]//Flatten (* _Harvey P. Dale_, Aug 23 2017 *)

%Y Cf. A129081; A000040; A030433.

%K easy,base,less,nonn

%O 1,2

%A _Tomas Xordan_, May 14 2007