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%I #11 Oct 22 2013 12:26:16
%S 1,2,1,2,1,2,1,2,2,2,1,2,5,2,1,4,2,2,1,2,3,3,1,3,2,3,4,2,2,2,1,2,3,3,
%T 1,3,1,5,2,5,5,4,4,2,2,2,1,2,2,2,1,2,2,4,1,5,5,6,6,3,2,3,2,5,4,2,2,2,
%U 1,2,2,5,6,4,5,2,4,3,13,2,4,5,5,2,10,4,3,14,3,11,8,4,2,4,1,7,6,3,2,3,2,2,1,2,2,3,2,2,1,2,6,4,3,8,3,4,2,3,1,11,9,6,4,7,13
%N Sequence of pairs k>0 and j>1 with the smallest j and the smallest sum j+k such that (k*j^n+1)*k*j^n-1 is prime.
%H Pierre CAMI, <a href="/A227903/b227903.txt">Table of n, a(n) for n = 1..4000</a>
%o PFGW & SCRIPTIFY
%o SCRIPT
%o DIM n,0
%o DIM j
%o DIM k
%o DIM ss
%o DIMS tt
%o OPENFILEOUT myf,a(n).txt
%o LABEL a
%o SET n,n+1
%o IF n>2000 THEN END
%o SET ss,2
%o LABEL b
%o SET ss,ss+1
%o SET j,1
%o LABEL c
%o SET j,j+1
%o SET k,ss-j
%o IF k<1 THEN GOTO b
%o SETS tt,%d,%d,%d\,;n;k;j
%o PRP (k*j^n+1)*k*j^n-1,tt
%o IF ISPRP THEN GOTO d
%o GOTO c
%o LABEL d
%o WRITE myf,tt
%o GOTO a
%Y Cf. A156051, A230259.
%K nonn
%O 1,2
%A _Pierre CAMI_, Oct 15 2013
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