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Primes of the form: nonprime(prime(n)) + n.
1

%I #8 Feb 02 2015 05:31:12

%S 2,11,79,97,109,127,151,239,313,557,599,661,719,733,797,839,1051,1061,

%T 1097,1171,1259,1283,1303,1453,1559,1621,1973,1999,2011,2111,2213,

%U 2267,2311,2383,2437,2539,2621,2719,2767,2879,2957,3083,3137,3313,3433,3607

%N Primes of the form: nonprime(prime(n)) + n.

%C Where n-th "prime nonprime"=A141468(A000040(n)) and 1st "prime nonprime" = 0.

%e For n=1, nonprime(prime(1))+1 = nonprime(2)+1 = 1+1 = 2 (prime), so a(1)=2.

%e For n=2, nonprime(prime(2))+2 = nonprime(3)+2 = 4+2 = 6 (composite).

%e For n=3, nonprime(prime(3))+3 = nonprime(5)+3 = 8+3 = 11 (prime), so a(2)=11, etc.

%p A154273 := proc(n) c := A141468(ithprime(n)) ; p := n+c ; if isprime(p) then printf("%d,",p) ; end if; end proc: seq(A154273(n),n=1..700) ; # _R. J. Mathar_, May 01 2010

%Y Cf. A000040, A141468.

%K nonn

%O 1,1

%A _Juri-Stepan Gerasimov_, Jan 06 2009

%E Corrected (787 replaced by 797) and extended by _R. J. Mathar_, May 01 2010