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%I #9 Sep 08 2022 08:46:11
%S 7,17,43,71,79,97,107,139,179,197,223,269,277,283,313,317,337,349,401,
%T 409,431,439,457,491,521,673,743,761,787,809,827,839,853,881,907,1021,
%U 1039,1061,1087,1151,1193,1213,1277,1303,1373,1399,1429,1447,1471,1483
%N Primes p such that p + nextprime(p) is divisible by 9.
%H Harvey P. Dale, <a href="/A253973/b253973.txt">Table of n, a(n) for n = 1..1000</a>
%e p=43 is in this sequence because 43+47 = 90 is divisible by 9.
%t Prime@Select[Range[300], Mod[Prime[#] + Prime[# + 1], 9]==0 &]
%t Select[Partition[Prime[Range[300]],2,1],Divisible[Total[#],9]&][[All,1]] (* _Harvey P. Dale_, Jul 27 2017 *)
%o (Magma) [p: p in PrimesUpTo(1500) | (p+NextPrime(p)) mod 9 eq 0];
%o (PARI) forprime(p=1,10^3,if(!((p+nextprime(p+1))%9),print1(p,", "))) \\ _Derek Orr_, Jan 30 2015
%Y Cf. similar sequences listed in A253969.
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Jan 28 2015
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