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%I #7 Aug 01 2015 21:40:27
%S 0,9,15,21,25,26,27,33,34,35,39,45,49,50,51,55,56,57,63,64,65,69,75,
%T 76,77,81,85,86,87,91,92,94,95,99,105,111,115,116,118,120,122,124,125,
%U 129,133,134,135,141,142,144,146,147,153,154,155,159,160,161,165,169,170
%N Numbers whose distance to the closest prime number is a prime number.
%C Terms n=2..31 are identical to terms n=1..30 of A079364.
%H K. Stern, <a href="/A160666/b160666.txt">Table of n, a(n) for n=1..10000</a>
%p isA160666 := proc(n) local ppl,pmi ; if isprime(n) then RETURN(false): elif n =0 then RETURN(true): elif n =1 then RETURN(false): fi; ppl := nextprime(n)-n ; pmi := n-prevprime(n) ; RETURN (isprime(min(ppl,pmi)) ) ; end: for n from 0 to 200 do if isA160666(n) then printf("%d,",n) ; fi; od: # _R. J. Mathar_, May 25 2009
%t fQ[n_] := PrimeQ[ Min[ NextPrime[n] - n, n - NextPrime[n, -1]]]; Select[ Range[0, 174], !PrimeQ@ # && fQ@# &] (* _Robert G. Wilson v_, May 25 2009 *)
%Y Cf. A000040, A051699.
%K nonn
%O 1,2
%A _Kyle Stern_, May 22 2009
%E More terms from _R. J. Mathar_ and _Robert G. Wilson v_, May 25 2009
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