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A166003 Primes p such that p+-1, p+-2 and p+-3 are not squarefree. 5
47527, 186247, 218527, 245149, 269953, 377543, 390449, 432277, 447823, 453053, 469649, 518123, 568177, 584911, 589273, 606323, 632347, 661547, 761347, 831751, 848213, 897577, 913327, 925949, 952253, 1172351, 1205647, 1220347, 1241477 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

MATHEMATICA

f[n_]:=Max[Last/@FactorInteger[n]]; q=2; lst={}; Do[p=Prime[n]; If[f[p-3]>=q&&f[p-2]>=q&&f[p-1]>=q&&f[p+1]>=q&&f[p+2]>=q&&f[p+3]>=q, AppendTo[lst, p]], {n, 6*8!}]; lst

Select[Prime[Range[100000]], NoneTrue[#+{-3, -2, -1, 1, 2, 3}, SquareFreeQ]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Apr 17 2018 *)

CROSSREFS

Cf. A086708, A086709, A089199, A089200, A089212, A166000, A166001, A166002.

Sequence in context: A069370 A241221 A261339 * A221017 A254800 A254807

Adjacent sequences: A166000 A166001 A166002 * A166004 A166005 A166006

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Oct 03 2009

EXTENSIONS

Edited by N. J. A. Sloane, Oct 04 2009

STATUS

approved

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Last modified February 1 08:20 EST 2023. Contains 359992 sequences. (Running on oeis4.)