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A155140 Primes p such that both p-+4 are not squarefree. 5
293, 347, 571, 829, 1021, 1229, 1327, 1373, 1471, 1621, 2111, 2129, 2371, 2531, 2579, 2879, 2887, 3181, 3271, 3929, 4621, 4801, 4909, 5279, 5333, 5521, 5639, 5683, 5827, 6133, 6421, 6521, 6709, 6863, 6871, 7079, 7321, 7529, 7591, 8179, 8221, 8429, 8963 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

John Cerkan, Table of n, a(n) for n = 1..10000

MATHEMATICA

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

PROG

(PARI) lista(nn) = forprime(p=2, nn, if (! issquarefree(p-4) && ! issquarefree(p+4), print1(p, ", "))); \\ Michel Marcus, Jul 05 2016

CROSSREFS

Cf. A153213, A049282, A155139, A155141, A155142.

Sequence in context: A232280 A202888 A217181 * A248210 A142284 A245583

Adjacent sequences: A155137 A155138 A155139 * A155141 A155142 A155143

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Jan 21 2009

STATUS

approved

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Last modified December 7 12:12 EST 2022. Contains 358656 sequences. (Running on oeis4.)