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a(n) = prime(n+7) - prime(n).
11

%I #20 Sep 08 2022 08:44:50

%S 17,20,24,24,26,28,26,28,30,30,30,30,30,30,32,30,30,36,34,32,34,30,30,

%T 38,34,36,36,42,42,44,36,36,36,40,32,40,36,34,32,38,44,46,38,40,42,42,

%U 40,34,36,40,38,38,40,32,36,44,42,42,40,50,54,54,42,42,46,50,42

%N a(n) = prime(n+7) - prime(n).

%H Reinhard Zumkeller, <a href="/A031169/b031169.txt">Table of n, a(n) for n = 1..10000</a>

%p ithprime(n+7)-ithprime(n);

%t #[[8]]-#[[1]]&/@Partition[Prime[Range[80]],8,1] (* _Harvey P. Dale_, Sep 16 2020 *)

%o (Magma) [NthPrime(n+7)-NthPrime(n): n in [1..100] ]; // _Vincenzo Librandi_, Apr 23 2011

%o (Haskell)

%o a031169 n = a031169_list !! (n-1)

%o a031169_list = zipWith (-) (drop 7 a000040_list) a000040_list

%o -- _Reinhard Zumkeller_, Aug 23 2015

%Y Cf. A000040, A001223, A031131, A031165, A031166, A031167, A031168, A031170, A031171, A031172.

%K nonn

%O 1,1

%A _Jeff Burch_

%E Offset changed from 2 to 1 and a(1)=17 inserted by _Vincenzo Librandi_, Apr 23 2011