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A268614 Primes p such that p + 1 and p + 2 are squarefree. 0
5, 13, 29, 37, 41, 101, 109, 113, 137, 157, 181, 193, 229, 257, 281, 317, 353, 389, 397, 401, 409, 433, 461, 509, 541, 569, 613, 617, 641, 653, 661, 677, 757, 761, 769, 797, 821, 829, 857, 877, 937, 941, 977, 1009, 1021, 1093, 1109, 1117, 1129, 1153, 1193 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

All terms are == 1 mod 4, hence in all cases p+3 is divisible by 4 (and is not squarefree).

LINKS

Table of n, a(n) for n=1..51.

MATHEMATICA

Select[Prime[Range[1000]], SquareFreeQ[# + 1] && SquareFreeQ[# + 2] &]

PROG

(MAGMA) [p: p in PrimesUpTo(1500) | IsSquarefree(p+1) and IsSquarefree(p+2)]; // Vincenzo Librandi, Feb 09 2016

CROSSREFS

Intersection of A049097 and A049233.

Sequence in context: A224339 A133204 A207040 * A152658 A100877 A261580

Adjacent sequences:  A268611 A268612 A268613 * A268615 A268616 A268617

KEYWORD

nonn

AUTHOR

Zak Seidov, Feb 08 2016

STATUS

approved

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Last modified October 17 22:48 EDT 2018. Contains 316297 sequences. (Running on oeis4.)