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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.)