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a(n) is the smallest prime of the form prime(n)*q + prime(n) + q, where q is an odd prime.
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%I #18 May 14 2013 13:25:13

%S 11,23,23,31,47,83,71,79,191,179,127,151,167,263,191,431,239,743,271,

%T 431,443,479,503,359,587,1223,1871,431,439,683,6143,1583,827,839,599,

%U 607,631,983,2351,2087,719,727,1151,1163,1187,2399,2543,2687,911,919

%N a(n) is the smallest prime of the form prime(n)*q + prime(n) + q, where q is an odd prime.

%C The odd primes q minimizing prime(n)*q + prime(n) + q are listed in A225581.

%H John-Å. W. Olsen, <a href="/A225587/b225587.txt">Table of a(n), for n = 1..1000</a>

%F a(n) = (1+prime(n))*A225581(n) + prime(n).

%e a(1) = 11 because prime(1) = 2 and the minimal prime of the form 2*q+2+q with q an odd prime is 11 = 2*3+2+3.

%t a[n_] := Block[{q = 3, v, p = Prime@n},While[! PrimeQ[v = p q + p + q], q = NextPrime@q]; v]; Array[a, 50] (* _Giovanni Resta_, May 11 2013 *)

%Y Cf. A225581, A000040.

%K nonn,easy

%O 1,1

%A _John-Å. W. Olsen_, May 11 2013

%E a(26)-a(50) from _Giovanni Resta_, May 11 2013