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 A093245 a(n) is the lesser term of the smallest twin prime pair such that if P=(a(n)^2+n)^2+n, then P and P+2 are also twin primes. 1

%I

%S 3,71,0,419,71,0,5,11,0,10271,24977,0,29,6869,0,3,9011,0,881,29,0,641,

%T 17,0,41,107,0,17,179,0,5,2801,0,10859,11,0,59,40637,0,461,17957,0,

%U 431,431,0,24977,5,0,12611,599,0,9431,1091,0,107,5867,0,3,15731,0,5,659,0

%N a(n) is the lesser term of the smallest twin prime pair such that if P=(a(n)^2+n)^2+n, then P and P+2 are also twin primes.

%C Note that either P or P+2 is composite whenever n is a multiple of 3 and in this case a(n)=0.

%e a(5) = 71: 71 and 73 are twin primes. (71^2+5)^2+5 = 25462121. 25462121 and 25462123 are also twin primes.

%t f[n_] := Block[{k = 2}, If[ Mod[n, 3] != 0, While[ p = Prime[k]; q = (p^2 + n)^2 + n; !PrimeQ[p + 2] || !PrimeQ[q] || !PrimeQ[q + 2], k++ ]; p, 0]]; Table[ f[n], {n, 63}] (from Robert G. Wilson v Sep 02 2004)

%Y Cf. A093189.

%K nonn

%O 1,1

%A _Ray G. Opao_, May 11 2004

%E Corrected and extended by _Robert G. Wilson v_, Sep 2 2004

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