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a(n) = 2*prime(n+2) - prime(n+1) - prime(n).
3

%I #23 Jul 31 2024 01:34:17

%S 5,6,10,8,10,8,10,16,10,14,14,8,10,16,18,10,14,14,8,14,14,16,22,16,8,

%T 10,8,10,32,22,16,10,22,14,14,18,14,16,18,10,22,14,10,8,26,36,20,8,10,

%U 16,10,22,22,18,18,10,14,14,8,22,38,22,8,10,32,26,26,14

%N a(n) = 2*prime(n+2) - prime(n+1) - prime(n).

%C For n > 2, all terms >= 8 and all even integers are possible except for 12.

%H Zak Seidov, <a href="/A191472/b191472.txt">Table of n, a(n) for n = 1..1000</a>

%H Charles R Greathouse IV, <a href="/A191472/a191472_1.txt">Record values</a>

%e a(1) = 2*prime(3) - prime(2) - prime(1) = 2*5 - 3 - 2 = 5.

%t ps = Prime[Range[100]]; Table[2*ps[[n+2]] - ps[[n+1]] - ps[[n]], {n, Length[ps] - 2}] (* _T. D. Noe_, Aug 27 2012 *)

%t 2#[[3]]-#[[2]]-#[[1]]&/@Partition[Prime[Range[70]],3,1] (* _Harvey P. Dale_, Aug 10 2023 *)

%t ListConvolve[{2, -1, -1}, Prime[Range[100]]] (* _Paolo Xausa_, Jul 30 2024 *)

%o (PARI) first(n)=my(v=vector(n),p=2,q=3,k); forprime(r=5,, if(k++>n, break); v[k]=2*r-q-p; p=q; q=r); v \\ _Charles R Greathouse IV_, Oct 03 2017

%Y Cf. A096379.

%K nonn

%O 1,1

%A _Zak Seidov_, Aug 27 2012