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%I #10 Mar 04 2013 12:58:15
%S 2,12,6,60,78,336,18,216,96,144,120,18,510,516,336,66,60,420,144,570,
%T 570,270,120,156,54,102,102,540,504,48,582,264,210,156,156,78,30,282,
%U 354,240,156,372,24,102,150,180,306,690,120,210,204,252,144,156,240,156
%N Least number k such that k*p(j)*p(j+1) - 1 and k*p(j)*p(j+1) + 1 are twin primes with p(j) and p(j+1) odd twin primes.
%H Harvey P. Dale, <a href="/A107414/b107414.txt">Table of n, a(n) for n = 1..1000</a>
%e 2*3*5=30 29 and 31 twin primes, 3 and 5 first odd twin primes so k(1)=2
%e 12*5*7=420 419 and 421 twin primes, 5 and 7 second odd twin primes so k(2)=12
%e 6*11*13=858 857 and 859 twin primes, 11 and 13 third odd twin primes k(3)=6
%t Module[{tp=Times@@@Select[Partition[Prime[Range[500]],2,1] ,#[[2]]-#[[1]] == 2&],len,k},len=Length[tp];Table[k=1;While[!And@@PrimeQ[k*tp[[n]]+{1,-1}],k++];k,{n,len}]] (* _Harvey P. Dale_, Mar 04 2013 *)
%K easy,nonn
%O 1,1
%A _Pierre CAMI_, May 26 2005
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