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A092954 Index of the first occurrence of n in A092953. There are a(n) primes p < n such that n+p is a prime.

%I A092954 #10 Jul 15 2018 13:04:20
%S A092954 1,3,8,12,26,40,24,48,42,54,110,60,140,84,160,90,132,126,162,120,168,
%T A092954 216,204,222,246,180,264,252,240,210,366,342,270,396,300,414,336,516,
%U A092954 850,558,330,462,534,552,390,504,450,1040,540,588,420,594,708,510,876
%N A092954 Index of the first occurrence of n in A092953. There are a(n) primes p < n such that n+p is a prime.
%H A092954 Reinhard Zumkeller, <a href="/A092954/b092954.txt">Table of n, a(n) for n = 0..1000</a>
%e A092954 a(6) = 24 as there are 6 values the prime p can take, 5, 7, 13, 17, 19 and 23 < 24 so that 24 + p is also prime.
%o A092954 (PARI) {stop=1050;m=56;v=vector(m,x,-1);for(n=1,stop,c=0;forprime(p=2,n-1,if(isprime(n+p),c++)); if(c<m&&v[c+1]<0,v[c+1]=n));for(j=1,m,print1(v[j],","))}
%o A092954 (Haskell)
%o A092954 import Data.List (elemIndex)
%o A092954 import Data.Maybe (fromJust)
%o A092954 a092954 = (+ 1) . fromJust . (`elemIndex` a092953_list)
%o A092954 -- _Reinhard Zumkeller_, Nov 10 2012
%Y A092954 Cf. A092953.
%K A092954 nonn
%O A092954 0,2
%A A092954 _Amarnath Murthy_, Mar 24 2004
%E A092954 More terms from _Klaus Brockhaus_ and Mohammed Bouayoun (bouyao(AT)wanadoo.fr), Mar 25 2004