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A058867
Equidistant lonely primes. Each prime is the same distance (gap) from the preceding prime and the next prime. These distances are maximal: each distance is larger than all such previous distances.
3
5, 53, 211, 16787, 69623, 247141, 3565979, 4911311, 12012743, 23346809, 34346287, 36598607, 51042053, 383204683, 4470608101, 5007182863, 5558570491, 48287689717, 50284155289, 178796541817, 264860525507, 374787490919, 1521870804107, 2093308790851, 4228611064537, 6537587646671, 17432065861517, 22546768250359, 26923643849953, 187891466722913
OFFSET
1,1
EXAMPLE
47, 53 and 59 are primes. There are no other primes between 47 and 59 and 59-53=53-47=6. There are no other such primes with a smaller distance so 53 is included in the sequence.
MAPLE
Primes:= select(isprime, [2, seq(2*i+1, i=1..10^7)]):
g:= 0: count:= 0:
for i from 2 to nops(Primes)-1 do
if Primes[i+1]+Primes[i-1] = 2*Primes[i] and Primes[i+1]-Primes[i] > g then
count:= count+1;
a[count]:= Primes[i];
g:= Primes[i+1]-Primes[i];
fi
od:
seq(a[i], i=1..count); # Robert Israel, Sep 20 2015
CROSSREFS
The distances are in A058868. First occurrences of distances are in A054342.
Sequence in context: A094849 A094852 A267543 * A058869 A054342 A216533
KEYWORD
nonn
AUTHOR
Harvey Dubner (harvey(AT)dubner.com), Dec 07 2000; extended Sep 11 2004
EXTENSIONS
a(21)-a(30) from Dmitry Petukhov, Sep 22 2015
STATUS
approved