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%I #6 Jan 09 2016 17:32:21
%S 269,293,317,389,509,557,653,773,797,1109,1229,1399,1447,1493,1543,
%T 1579,1627,1637,1663,1699,1733,1759,1867,1879,1949,1987,1997,2083,
%U 2203,2239,2309,2383,2477,2659,2693,2767,2803,2837,2909,2957,3019,3343,3413,3463
%N Primes p such that p-1 has a prime factor q with (p-1)/2 > q > p^(3/4).
%H Harvey P. Dale, <a href="/A073026/b073026.txt">Table of n, a(n) for n = 1..1000</a>
%p a := []; for i from 2 to 1000 do p := ithprime(i); t1 := factorset(p-1); q := t1[nops(t1)]; if q^4 >= p^3 and q < (p-1)/2 then a := [op(a),p]; fi; od:
%t pfQ[n_]:=Module[{pfs=Transpose[FactorInteger[n-1]][[1]]},MemberQ[((n-1)/2>#>n^(3/4))&/@pfs,True]]; Select[Prime[Range[500]],pfQ] (* _Harvey P. Dale_, Jan 09 2016 *)
%Y Cf. A005384, A005385, A073024, A073025.
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Aug 23 2002
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