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Prime(n)+even nonprime(n) is prime.
0

%I #6 Apr 15 2014 00:36:02

%S 1,2,3,7,9,11,12,13,14,18,24,27,28,29,30,36,38,43,44,53,54,55,57,60,

%T 63,64,65,66,72,74,80,84,90,93,102,103,108,110,111,117,118,125,126,

%U 135,138,141,143,148,150,155,156,162,165,171,174,180,183,186,188,190,198

%N Prime(n)+even nonprime(n) is prime.

%C Unit together with prime(n)+s*n is prime, s=2.

%F a(n+1)=A076297(n).

%e 1 is in the sequence because A000040(1) + A163300(1) = 2 (1st prime) + 0 (1st even nonprime) is prime;

%e 2 is in the sequence because A000040(2) + A163300(2) = 3 (2nd prime) + 4 (2nd even nonprime) is prime.

%p From _R. J. Mathar_, Apr 20 2010: (Start)

%p A163300 := proc(n) option remember ; if n = 1 then 0; else for a from procname(n-1)+2 by 2 do if not isprime(a) then return a ; end if; end do; end if; end proc:

%p for n from 1 to 200 do if isprime( ithprime(n) + A163300(n)) then printf("%d,",n) ; end if; end do: (End)

%Y Cf. A000040, A076297, A163300.

%K nonn

%O 1,2

%A _Juri-Stepan Gerasimov_, Mar 11 2010

%E Entries checked by _R. J. Mathar_, Apr 20 2010