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A153215 Primes p such that p+-1 and p+-2 are NotSquarefree. 0
727, 1423, 1861, 3719, 6173, 9749, 11321, 13183, 19073, 20873, 23227, 23473, 23827, 26981, 27883, 34351, 35323, 41263, 42677, 44449, 45127, 45523, 47527, 48751, 49727, 52391, 53623, 53849, 68749, 71993, 72559, 78823, 83609, 89227, 92779 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

MAPLE

f[n_]:=Max[Last/@FactorInteger[n]]; q=2; lst={}; Do[p=Prime[n]; If[f[p-2]>=q&&f[p-1]>=q&&f[p+1]>=q&&f[p+2]>=q, AppendTo[lst, p]], {n, 4*7!}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Oct 03 2009]

MATHEMATICA

<< NumberTheory`NumberTheoryFunctions` lst={}; Do[p=Prime[n]; If[ !SquareFreeQ[p-1]&&!SquareFreeQ[p+1]&&!SquareFreeQ[p-2]&&!SquareFreeQ[p+2], AppendTo[lst, p]], {n, 4*7!}]; lst

CROSSREFS

Cf. A049282, A049097, A039787, A075432, A153207, A153208, A153209, A153210, A153213, A153214

Sequence in context: A108846 A052234 A103170 * A129117 A158394 A038600

Adjacent sequences:  A153212 A153213 A153214 * A153216 A153217 A153218

KEYWORD

nonn

AUTHOR

Vladimir Orlovsky (4vladimir(AT)gmail.com), Dec 20 2008

EXTENSIONS

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Last modified February 17 02:31 EST 2012. Contains 205978 sequences.