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%I #21 Apr 10 2013 12:13:17
%S 48497,48907,493747,578453,1223777,1249363,1933363,3304607,5160217,
%T 5765083,6022087,6205937,7740127,7757447,7862843,8173537,8938627,
%U 11989177,13789033,17649223,18142693,18829117,20006813,20601593,23938867,24448063,24478043
%N Odd primes p(i) such that 6*p(i+j)^2-1 is also prime for j = 0..3.
%H Pierre CAMI, <a href="/A223935/b223935.txt">Table of n, a(n) for n = 1..131</a>
%e p(4990)=48497 and 6*48497*48497-1=14111754053 is prime,
%e p(4991)=48523 and 6*48523*48523-1=14126889173 is prime,
%e p(4992)=48527 and 6*48527*48527-1=14129218373 is prime,
%e p(4993)=48533 and 6*48533*48533-1=14132712533 is prime,
%e so a(1)=p(4990)=48497
%t Reap[ For[ n=1; i=2, i < 5*10^6, i++, If[And @@ PrimeQ /@ Table[p[j] = Prime[i+j]; 6*p[j]^2-1, {j, 0, 3}], Print["i = ", i, " a(", n, ") = ", p[0]]; n++; Sow[ p[0] ] ] ] ][[2, 1]] (* _Jean-François Alcover_, Apr 09 2013 *)
%o PFGW and SCRIPTIFY
%o SCRIPT
%o DIM i,4000
%o DIMS t
%o OPENFILEOUT myf,res.txt
%o LABEL loop1
%o SET i,i+1
%o IF i==9999997 THEN END
%o SETS t,%d,%d\,;i;p(i)
%o PRP 6*p(i)*p(i)-1,t
%o IF ISPRP THEN GOTO a
%o GOTO loop1
%o LABEL a
%o SET i,i+1
%o SETS t,%d,%d\,;i;p(i)
%o PRP 6*p(i)*p(i)-1,t
%o IF ISPRP THEN GOTO b
%o GOTO loop1
%o LABEL b
%o SET i,i+1
%o SETS t,%d,%d\,;i;p(i)
%o PRP 6*p(i)*p(i)-1,t
%o IF ISPRP THEN GOTO c
%o GOTO loop1
%o LABEL c
%o SET i,i+1
%o SETS t,%d,%d\,;i;p(i)
%o PRP 6*p(i)*p(i)-1,t
%o IF ISPRP THEN WRITE myf,t
%o GOTO loop1
%K nonn
%O 1,1
%A _Pierre CAMI_, Mar 29 2013
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