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%I #10 Apr 09 2018 15:21:14
%S 2,4,9,15,21,30,39,45,56,64,72,81,93,102,108,120,134,144,154,165,176,
%T 186,195,205,225,231,240,254,266,274,282,300,312,324,342,351,363,376,
%U 386,399,414,426,436,446,459,465,483,495,506,522,544,560,570,582,596
%N Average of consecutive primes.
%C 2 together with average of odd primes taken two at a time without overlaps, i.e., 2 together with average of (3,5), (7,11), (13,17), etc. - _Harvey P. Dale_, Apr 09 2018
%H Harry J. Smith, <a href="/A058296/b058296.txt">Table of n, a(n) for n = 1..20000</a>
%H Donald Mills, <a href="http://www.math.siu.edu/mills/interesting_seqs.pdf">Some Interesting Sequences</a>.
%F a(1)=2, a(n) = (p(2n-2) + p(2n-1))/2 for n>1, where p(i) is the i-th prime.
%p with(linalg): v := linalg[vector](100): v[1] := 2: for j from 2 to 100 do v[j] := (ithprime(2*j-2)+ithprime(2*j-1))/2: od: print(v);
%t Join[{2},Mean/@Partition[Prime[Range[2,121]],2]] (* _Harvey P. Dale_, Apr 09 2018 *)
%o (PARI) { write("b058296.txt", 1, " ", 2); p2=2; for (n=2, 20000, p1=nextprime(p2+1); p2=nextprime(p1+1); a=(p1+p2)/2; write("b058296.txt", n, " ", a); ); } \\ _Harry J. Smith_, May 30 2009
%Y A bisection of A024675. Cf. A079424.
%K easy,nonn
%O 1,1
%A Donald Mills (dmills(AT)math.siu.edu), Feb 16 2003
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