A073026 Primes p such that p-1 has a prime factor q with (p-1)/2 > q > p^(3/4).

269, 293, 317, 389, 509, 557, 653, 773, 797, 1109, 1229, 1399, 1447, 1493, 1543, 1579, 1627, 1637, 1663, 1699, 1733, 1759, 1867, 1879, 1949, 1987, 1997, 2083, 2203, 2239, 2309, 2383, 2477, 2659, 2693, 2767, 2803, 2837, 2909, 2957, 3019, 3343, 3413, 3463

Offset

1,1

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Maple

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:

Mathematica

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 *)

Crossrefs

Cf. A005384, A005385, A073024, A073025.

Sequence in context: A073522 A273552 A341181 * A255206 A142636 A142385

Adjacent sequences: A073023 A073024 A073025 * A073027 A073028 A073029

Keyword

nonn

Author

N. J. A. Sloane, Aug 23 2002

Status

approved