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 A155215 a(n) is the average of the smallest prime greater than n and largest prime smaller than n + prime(n). 1

%I #8 Apr 17 2013 10:15:09

%S 2,3,6,6,10,12,17,17,21,24,27,30,35,35,39,42,46,46,53,56,56,60,66,69,

%T 71,71,78,80,84,85,97,97,102,102,109,109,117,120,120,126,127,127,140,

%U 140,144,144,155,161,162,165,168,168,176,176,185,188,188,188,196

%N a(n) is the average of the smallest prime greater than n and largest prime smaller than n + prime(n).

%H Harvey P. Dale, <a href="/A155215/b155215.txt">Table of n, a(n) for n = 1..1000</a>

%e a(32)= 97. Smallest prime greater than 32 is 37 and p(32)=131, largest prime smaller than 32+p(32) or 163 is 157. So (37+157)/2 = 97

%t Table[(NextPrime[n]+NextPrime[n+Prime[n],-1])/2,{n,100}] (* _Harvey P. Dale_, Apr 17 2013 *)

%K nonn

%O 1,1

%A Avik Roy (avik_3.1416(AT)yahoo.co.in), Jan 22 2009

%E Corrected by _Harvey P. Dale_, Apr 16 2013

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Last modified December 8 23:09 EST 2023. Contains 367680 sequences. (Running on oeis4.)