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%I #13 Apr 14 2021 05:24:12
%S 341,1387,2047,4681,13747
%N Base-2 pseudoprimes (see A001567) of the form j*p(i)# - p(k) or j*p(i)# + p(k), p(i) and p(k) primes with p(i) < p(k) < p(i+1)^2 and 0 < j < p(i+1).
%C Conjecture: sequence has only 5 terms. This has been checked for all i <= 150.
%H <a href="/index/Ps#pseudoprimes">Index entries for sequences related to pseudoprimes</a>
%e 2*7# - 79 = 341,
%e 7*7# - 83 = 1387,
%e 10*7# - 53 = 2047,
%e 2*11# + 61 = 4681,
%e 6*11# - 113 = 13747,
%e 13*7# - 29 = 2701.
%o (PARI) lst(lim)=my(p=2,P=1,v=List());forprime(q=3,lim,P*=p;forprime(r=q, q^2, for(j=1,q-1,if(j*P-r>340&&psp(j*P-r),listput(v,j*P-r)); if(psp(j*P+r),listput(v,j*P+r))));p=q);vecsort(Vec(v),,8) \\ _Charles R Greathouse IV_, Apr 12 2012
%Y Cf. A001567, A087714, A087715, A087728.
%Y # denotes primorials; see A002110.
%K nonn,more
%O 1,1
%A _Pierre CAMI_, Sep 29 2003
%E Edited by _David Wasserman_, Apr 13 2006
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