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%I #6 Mar 31 2012 10:23:48
%S 7,10,19,20,24,25,26,32,38,39,40,43,44,45,47,51,53,55,56,57,61,63,65,
%T 66,68,69,74,81,84,86,87,88,89,90,91,92,94,96,97,98,99,101,106,109,
%U 110,111,113,114,115,116,117,123,124,125,129,130,131,132,134,135
%N a(n) is the prime order number of A196938.
%e A196938(1) = 17, which is the 7th prime, so a(1) = 7
%t i = 1; Table[While[i++; p = Prime[i]; found = 0; j = 0; While[j++; df = 6*j; (p > (2*df)) && (found == 0), cp1 = p - 2*df; cp2 = p - df; cp3 = p + df; cp4 = p + 2*df; If[(PrimeQ[cp1]) && (PrimeQ[cp2]) && (PrimeQ[cp3]) && (PrimeQ[cp4]), found = 1]]; found == 0]; i, {ct, 1, 60}]
%Y Cf. A196938.
%K nonn,easy
%O 1,1
%A _Lei Zhou_, Oct 07 2011