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 A061368 Lesser of twin primes (p, p+2) whose average p+1 is not squarefree. 1
 3, 11, 17, 59, 71, 107, 149, 179, 191, 197, 227, 239, 269, 311, 347, 419, 431, 521, 599, 659, 809, 827, 881, 1019, 1031, 1049, 1061, 1091, 1151, 1277, 1319, 1427, 1451, 1487, 1607, 1619, 1667, 1787, 1871, 1931, 1949, 1997, 2027, 2087, 2111, 2141, 2267 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Amiram Eldar, Table of n, a(n) for n = 1..10000 (terms 1..1000 from Harry J. Smith) FORMULA Intersection of A014574 and A013929. MATHEMATICA Select[Select[Partition[Prime[Range[400]], 2, 1], #[[2]]-#[[1]]==2&][[All, 1]], !SquareFreeQ[#+1]&] (* Harvey P. Dale, Oct 21 2016 *) PROG (PARI) { n=-1; forprime (p=2, 119099, if (isprime(p+2) && !issquarefree(p+1), write("b061368.txt", n++, " ", p)) ) } \\ Harry J. Smith, Jul 22 2009 (MAGMA) [p:p in PrimesUpTo(2500)| IsPrime(p+2) and not IsSquarefree(p+1)]; // Marius A. Burtea, Jan 16 2020 CROSSREFS Cf. A001359, A005117, A014574, A013929. Sequence in context: A245045 A127996 A032008 * A145701 A072982 A124787 Adjacent sequences:  A061365 A061366 A061367 * A061369 A061370 A061371 KEYWORD nonn,changed AUTHOR Labos Elemer, Jun 07 2001 EXTENSIONS Offset corrected by Amiram Eldar, Jan 16 2020 STATUS approved

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Last modified January 22 04:27 EST 2020. Contains 331133 sequences. (Running on oeis4.)