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 A069456 Non-twin primes that are at least doubly lonely. 3
 1039, 2099, 4253, 91121, 386401, 626617, 754973, 873553, 908857, 972137, 1619353, 1749067, 1841681, 2007899, 2169007, 2241353, 2420633, 2484931, 2594971, 3075323, 3129601, 3151843, 3837451, 3843247, 3919229, 4038709, 4545683, 5502449, 5530529, 5921869 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Arkadiusz Wesolowski, Table of n, a(n) for n = 1..10000 EXAMPLE These are non-twin primes sandwiched between at least 2 pairs of twins on each side. The first number in the sequence is 1039 (sandwiched between 1019,1021,1031,1033 and 1049,1051,1061,1063). MAPLE Primes:= select(isprime, [seq(i, i=3..6*10^6, 2)]): good:= select(t -> Primes[t-3]-Primes[t-4]=2 and Primes[t-1]-Primes[t-2]=2 and Primes[t+2]-Primes[t+1]=2 and Primes[t+4]-Primes[t+3]=2, [\$5..nops(Primes)-4]): Primes[good]; # Robert Israel, May 13 2016 MATHEMATICA dltpQ[{a_, b_, c_, d_, e_, f_, g_, h_, i_}]:=b-a==d-c==g-f==i-h==2; Transpose[ Select[ Partition[Prime[Range[410000]], 9, 1], dltpQ]][[5]] (* Harvey P. Dale, May 14 2013 *) CROSSREFS Cf. A007510, A069453. Sequence in context: A235156 A288413 A020395 * A210259 A233854 A168412 Adjacent sequences:  A069453 A069454 A069455 * A069457 A069458 A069459 KEYWORD nonn AUTHOR Neil Fernandez, Mar 23 2002 EXTENSIONS More terms from Arkadiusz Wesolowski, May 08 2012 STATUS approved

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Last modified May 13 14:47 EDT 2021. Contains 343860 sequences. (Running on oeis4.)