A031169 a(n) = prime(n+7) - prime(n).

17, 20, 24, 24, 26, 28, 26, 28, 30, 30, 30, 30, 30, 30, 32, 30, 30, 36, 34, 32, 34, 30, 30, 38, 34, 36, 36, 42, 42, 44, 36, 36, 36, 40, 32, 40, 36, 34, 32, 38, 44, 46, 38, 40, 42, 42, 40, 34, 36, 40, 38, 38, 40, 32, 36, 44, 42, 42, 40, 50, 54, 54, 42, 42, 46, 50, 42

Offset: 1

Author

Jeff Burch

Keywords

• nonn

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Crossrefs

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

Programs

Haskell

a031169 n = a031169_list !! (n-1)
a031169_list = zipWith (-) (drop 7 a000040_list) a000040_list
-- Reinhard Zumkeller, Aug 23 2015

Magma

[NthPrime(n+7)-NthPrime(n): n in [1..100] ]; // Vincenzo Librandi, Apr 23 2011

Maple

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

Mathematica

#[[8]]-#[[1]]&/@Partition[Prime[Range[80]],8,1] (* Harvey P. Dale, Sep 16 2020 *)

Extensions

Offset changed from 2 to 1 and a(1)=17 inserted by Vincenzo Librandi, Apr 23 2011